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refactor(curriculum): JS comparisons quiz (#58408)
Co-authored-by: Dario-DC <105294544+Dario-DC@users.noreply.github.com>
This commit is contained in:
Zaira
@@ -7,7 +7,7 @@ dashedName: quiz-javascript-comparisons-and-conditionals
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# --description--
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To pass the quiz, you must correctly answer at least 18 of the 20 questions below.
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To pass the quiz, you must correctly answer at least 9 of the 10 questions below.
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# --quizzes--
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@@ -17,33 +17,7 @@ To pass the quiz, you must correctly answer at least 18 of the 20 questions belo
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#### --text--
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What's the difference between `==` and `===`?
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#### --distractors--
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There is no difference, both have the exact same function.
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---
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`==` checks both values and its data type, while `===` only checks for value.
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---
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Both operators check the data type of the value, but only `===` compares values deeply.
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#### --answer--
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`===` compares the value and type without type coercion, while `==` attempts to convert them to the same type before comparing.
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### --question--
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#### --text--
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```js
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console.log(5 === "5");
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```
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What's the output of the code above?
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What's the result of the expression `undefined > 0`?
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#### --distractors--
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@@ -51,11 +25,11 @@ What's the output of the code above?
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---
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`NaN`
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`undefined`
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---
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An error is raised.
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`null`
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#### --answer--
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@@ -65,28 +39,6 @@ An error is raised.
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#### --text--
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Which of the following is NOT a comparison operator?
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#### --distractors--
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`===`
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---
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`!==`
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---
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`<=`
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#### --answer--
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`?==`
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### --question--
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#### --text--
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Which logical operation does `||` represent?
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#### --distractors--
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@@ -109,12 +61,12 @@ OR
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#### --text--
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What's the output of the following code?
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```js
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console.log(5 === 2 + 3 || 4 == 2);
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```
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What's the output of the code above?
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#### --distractors--
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`undefined`
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@@ -139,15 +91,15 @@ What is a truthy and falsy value?
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#### --distractors--
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Value that's both `true` and `false`.
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A value that's both `true` and `false`.
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---
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Value that changes depending on context.
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A value that changes depending on context.
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---
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Value that functions differently than `true` or `false` value.
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A value that functions differently than `true` or `false` value.
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#### --answer--
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@@ -157,14 +109,14 @@ A value that is considered `true` or `false` when encountered in a Boolean conte
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#### --text--
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What's logged to the console from the code below?
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```js
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if (1) {
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console.log("True!");
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}
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```
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What's printed to the console from the code above?
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#### --distractors--
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`false`
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@@ -179,29 +131,7 @@ An error is raised.
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#### --answer--
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`"True!"`
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### --question--
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#### --text--
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Which of the following is NOT a truthy value?
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#### --distractors--
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`"false"`
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---
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`13`
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---
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`-1`
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#### --answer--
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`0`
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`True!`
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### --question--
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@@ -211,11 +141,11 @@ What's the difference between `undefined` and `null`?
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#### --distractors--
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No difference.
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`null` and `undefined` point to an out-of-range memory location and are inaccessible.
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---
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`null` is the implicit value assigned to variables.
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`null` is the implicit value assigned to variables and it can not be changed, while `undefined` is the explicit value assigned to variables.
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---
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@@ -223,146 +153,35 @@ No difference.
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#### --answer--
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Variables not assigned a value has the value `undefined`, while `null` is used to represent the intentional absence of any object value.
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Variables without a value are `undefined`, while `null` represents an intentional absence of an object value.
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### --question--
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#### --text--
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```js
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const a = Boolean(undefined);
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```
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The value of `a` in the code above is...
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What happens when you don't include `break` while implementing a `switch` statement?
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#### --distractors--
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`undefined`
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The `switch` statement will stop abruptly.
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---
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`true`
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The `switch` statement will throw an error after previous statement.
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---
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`NaN`
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The `switch` statement will exit after the first match.
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#### --answer--
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`false`
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The code continues to evaluate the following `case` statements, even after finding a match.
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### --question--
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#### --text--
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```js
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if (2 == 2) {
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console.log("A");
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} else {
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console.log("B");
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}
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```
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What's printed to the console when the code above executes?
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#### --distractors--
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An error is raised.
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---
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`"B"`
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---
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Nothing gets printed to the console.
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#### --answer--
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`"A"`
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### --question--
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#### --text--
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```js
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if (2 == "2") {
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// Statement.
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}
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```
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What will happen when the code is ran?
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#### --distractors--
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The statement will output a warning and exits the program.
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---
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The statement will not run.
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---
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The statement will throw an error.
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#### --answer--
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The statement will run.
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### --question--
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#### --text--
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```js
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if (2 == "2") {
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const a = 2;
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}
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console.log(a);
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```
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What is printed to the console with code above?
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#### --distractors--
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`2`
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---
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Nothing gets printed.
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---
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`undefined`
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#### --answer--
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An error is raised.
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### --question--
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#### --text--
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What happens when you don't include `break` while implementing a switch statement?
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#### --distractors--
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The switch statement will stop abruptly.
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---
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The switch statement will throw an error after previous statement.
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---
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The switch statement will exit after the first match.
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#### --answer--
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The code continues to evaluate the following case statements, even after finding a match.
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### --question--
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#### --text--
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What is printed to the console from the code below?
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```js
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const a = 2;
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@@ -373,8 +192,6 @@ if (1 == "1") {
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console.log(b);
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```
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What will be printed to the console from the code above?
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#### --distractors--
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An error is raised.
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@@ -401,49 +218,57 @@ undefined
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#### --text--
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What keyword is used in a switch statement to handle cases when all of the specified cases are false?
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What will be the output of the following JavaScript code?
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```js
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let vehicle = "car";
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switch (vehicle) {
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case "bike":
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console.log("Bikes are two-wheelers.");
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break;
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case "car":
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console.log("Some cars are 4x4.");
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case "truck":
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console.log("Trucks can carry heavy loads.");
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break;
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default:
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console.log("Unknown vehicle.");
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}
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```
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#### --distractors--
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`then`
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```md
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Some cars are 4x4.
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```
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---
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`after`
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```md
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Some cars are 4x4.
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Trucks can carry heavy loads.
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Unknown vehicle.
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```
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---
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`else`
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```md
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Unknown vehicle.
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```
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#### --answer--
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`default`
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```md
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Some cars are 4x4.
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Trucks can carry heavy loads.
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```
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### --question--
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#### --text--
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What does the operator `&&` represent?
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#### --distractors--
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XOR
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---
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OR
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---
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NOT
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#### --answer--
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AND
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### --question--
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#### --text--
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What is printed to the console with code below?
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```js
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let x = 5;
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@@ -454,8 +279,6 @@ if (x > 1 && x < 10) {
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}
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```
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What is printed to the console with code above?
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#### --distractors--
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An error is raised.
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@@ -466,57 +289,9 @@ Nothing is printed.
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---
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`"x is not between 1 and 10"`
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`x is not between 1 and 10`
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#### --answer--
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`"x is between 1 and 10"`
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### --question--
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#### --text--
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What does the operator `!` do?
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#### --distractors--
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It will reverse the value of a variable.
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---
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It will do "AND" operation.
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---
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It will do "OR" operation.
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#### --answer--
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It will negate the boolean value or converts a non-boolean expression to its opposite.
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### --question--
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#### --text--
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```js
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console.log(!!true);
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```
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What is printed to the console with the above code?
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#### --distractors--
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`false`
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---
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It raises an error, you can't double negate an expression.
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---
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`undefined`
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#### --answer--
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`true`
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`x is between 1 and 10`
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