JavaScript Essentials 1 (JSE) | JSE1 – Module 3 Test Exam Answers

JavaScript Essentials 1 (JSE) | JSE1 – Module 3 Test Exam Answers Full 100% 2023 2024

This is the JavaScript Essentials 1 (JSE) | JSE1 – Module 3 Test Exam Answers consisting of all questions and answers with a full score of 100% plus explanations. Our experts have received many questions from students day by day and update the answers here in JSE1 – Module 3 Test Exam Answers Cisco NetAcad SkillsForAll. You can practice and review all the questions and answers before you prepare for the exam. If you are unclear about something, you can comment below the page. We are happy to assist you.

3.3 Module 3 Completion – Module Test Exam Answers Full 100% 2023 2024

  1. The result of the operation 20 || 5 will be:

    • 5
    • 25
    • 20
    • true
    • Answers Explanation & Hints:

      In JavaScript, the double vertical bar “||” is indeed used as the logical OR operator. The logical OR operator in JavaScript returns the first operand if it is truthy, otherwise, it returns the second operand.

      In the case of the expression “20 || 5”, both 20 and 5 are considered truthy values in JavaScript. Therefore, the result of the operation would be 20, which is the first truthy value encountered.

      To illustrate this in code:

      console.log(20 || 5); // Output: 20

      So, the result of the operation “20 || 5” in JavaScript is 20.

  2. The result of the operation false || "false" will be:

    • 0
    • "false"
    • false
    • true
    • Answers Explanation & Hints:

      The result of the operation false || "false" in JavaScript is indeed false.

      The logical OR operator (||) returns the first truthy value it encounters or the last operand if all operands are falsy. In this case, the first operand is false, which is falsy. The second operand is the string "false", which is also truthy. Since the logical OR operator did not encounter a truthy value in the operands before reaching the last operand, it returns the last operand, which is false.

      Therefore, the correct answer is false.

  3. The result of the operation 3 * 4 > 20 - 15 will be:

    • NaN
    • false
    • true
    • -14
    • Answers Explanation & Hints:

      To evaluate the expression “3 * 4 > 20 – 15,” let’s break it down:

      First, we calculate the values on both sides of the comparison:

      3 * 4 = 12 20 – 15 = 5

      Now we can compare the two values:

      12 > 5

      Since 12 is indeed greater than 5, the result of the comparison is true.

      Therefore, the correct answer is true.

  4. Which operator do we use if we want to check if two variables store the same values of exactly the same type?

    • =
    • ===
    • ==
    • !==
    • Answers Explanation & Hints:

      To check if two variables store the same values of exactly the same type in JavaScript, you would use the strict equality operator, which is “===”.

      Here’s an explanation of the different comparison operators you mentioned:

      • “===” (strict equality operator): It compares two values for equality without performing any type coercion. It returns true if the values are equal in value and type.
      • “==” (loose equality operator): It also compares two values for equality, but it allows for type coercion. JavaScript will try to convert the operands to the same type before making the comparison. This operator can lead to unexpected results due to the type coercion rules, so it’s generally recommended to use the strict equality operator (===) instead.
      • “!=” (loose inequality operator): It checks if two values are not equal after performing type coercion.
      • “!==” (strict inequality operator): It checks if two values are not equal without performing any type coercion.

      For comparing variables to check if they hold the same values of the same type, you should use the strict equality operator (===). For example:

      const variable1 = 5;
const variable2 = 5;

console.log(variable1 === variable2); // Output: true

      In the above example, both variable1 and variable2 hold the same value of 5, and since the strict equality operator is used, the comparison evaluates to true.

  5. The result of the operation !(true && false || true) will be:

    • null
    • false
    • 1
    • true
    • Answers Explanation & Hints:

      The result of the operation “!(true && false || true)” will be “false”.

      To evaluate this expression, let’s break it down step by step:

      1. The innermost part of the expression is the logical AND operation “true && false”, which evaluates to “false”. This is because both operands need to be true for the logical AND to return true.
      2. Next, we have the logical OR operation “false || true”, which evaluates to “true”. This is because at least one of the operands needs to be true for the logical OR to return true.
      3. Finally, we have the logical NOT operation “!true”, which negates the result and returns the opposite. Since the result of the previous step is “true”, the logical NOT operation returns “false”.

      Therefore, the result of the operation “!(true && false || true)” is “false”.

      To illustrate this in code:

      console.log(!(true && false || true)); // Output: false

      So, the correct answer is “false”.

  6. Analyze the following code:

    let test = prompt("Hello", "World");

    What value will the test variable have if, after running the code, we immediately press the Ok button on the newly created dialog?

    • true
    • "Hello"
    • "OK"
    • "World"
    • Answers Explanation & Hints:

      If, after running the code let test = prompt("Hello", "World");, you immediately press the “OK” button on the dialog without modifying the input, the test variable will have the value “World”.

      The prompt function in JavaScript displays a dialog box with an optional message and a default value. In this case, the message is “Hello” and the default value is “World”.

      When the dialog appears, if you click “OK” without modifying the input, the default value (“World”) will be assigned to the test variable.

      Here’s an example of what the code could look like and the outcome:

      let test = prompt("Hello", "World");
console.log(test);

      Scenario: User presses “OK” without modifying the input:

      • Dialog box appears with the default input “World”.
      • User presses “OK” without modifying the input.
      • The default value (“World”) will be assigned to the test variable.
      • The output will be “World”.

      Therefore, in this specific scenario, the test variable will have the value “World”.

  7. The number 2 is stored in the variable n (let n = 2;). The command n = n*n*n is then called. This last command can be replaced by:

    • n **= n;
    • n **= 3;
    • n *= 3;
    • n ***= n;
    • Answers Explanation & Hints:

      The command n = n * n * n can be replaced by n **= 3.

      In JavaScript, the **= operator is the exponentiation assignment operator. It raises the left-hand side operand to the power of the right-hand side operand and assigns the result back to the left-hand side variable.

      So, when n = n * n * n is replaced with n **= 3, it means n will be raised to the power of 3 and the result will be assigned back to n. It is equivalent to performing n = n ** 3.

      Here’s an example to illustrate this:

      let n = 2;
n **= 3;
console.log(n); // Output: 8

      In this case, the value of n is initially 2. After executing n **= 3, n is raised to the power of 3, resulting in 8. Therefore, the output will be 8.

      To summarize, the command n = n * n * n can be replaced by n **= 3 to achieve the same result.

  8. Analyze the code snippet:

    let n = 2 * 3 ** 3 - 1;

    The result is stored in the variable n is:

    • 18
    • 36
    • 215
    • 53
    • Answers Explanation & Hints:

      The result stored in the variable n after executing the code snippet let n = 2 * 3 ** 3 - 1; is 53.

      Let’s break down the code snippet step by step:

      1. 3 ** 3 is an exponentiation operation where 3 is raised to the power of 3. This results in 27.
      2. Next, 2 * 27 is multiplied, which gives 54.
      3. Finally, 54 - 1 is subtracted, resulting in 53.

      Therefore, the final value calculated is 53, and it is stored in the variable n.

      To illustrate this in code:

      let n = 2 * 3 ** 3 - 1;
console.log(n); // Output: 53

      So, the result stored in the variable n is 53.

  9. The result of the comparison "abcd" > "Abcd" will be:

    • "abcd"
    • true
    • false
    • 1
    • Answers Explanation & Hints:

      The result of the comparison "abcd" > "Abcd" will be true.

      When comparing strings in JavaScript using the greater-than operator (>), the comparison is made based on lexicographic order, which follows the Unicode values of the characters.

      In this case, comparing the strings “abcd” and “Abcd” character by character, the first differing characters are “a” and “A”. In Unicode, the lowercase letters have higher values than uppercase letters. Therefore, “a” is greater than “A” in lexicographic order.

      Since the first differing character (“a”) in the first string is greater than the corresponding character (“A”) in the second string, the comparison evaluates to true.

      To illustrate this in code:

      console.log("abcd" > "Abcd"); // Output: true

      So, the correct answer is true.

  10. Analyze the code snippet:

    let n = 10;
let m = ++n;

    Its execution will result in the following values in the variables n and m:

    • n: 11, m: 10
    • n: 10, m: 11
    • n: 11, m: 11
    • n: 10, m:10
    • Answers Explanation & Hints:

      The execution of the code snippet let n = 10; let m = ++n; will result in the following values in the variables n and m:

      • n will have a value of 11.
      • m will also have a value of 11.

      Let’s break down the code snippet step by step:

      1. Initially, the variable n is assigned the value of 10.
      2. The ++ operator before the variable n is the pre-increment operator. It increments the value of n by 1 before using it.
      3. Therefore, when ++n is executed, the value of n is incremented to 11.
      4. The value of n (which is now 11) is then assigned to the variable m.

      After the code snippet is executed, n will be 11 and m will also be 11.

      To illustrate this in code:

      let n = 10;
let m = ++n;
console.log(n); // Output: 11
console.log(m); // Output: 11

      So, the resulting values in the variables n and m will be 11 for both.

  11. The confirm method allows you to create a dialog box. What value does this method return when the user closes the window?

    • Always true.
    • Always false.
    • The string entered by the user.
    • It depends on the option selected by the user.
    • Answers Explanation & Hints:

      The confirm method in JavaScript allows you to create a dialog box with an OK and Cancel button. When the user interacts with the dialog box, the method returns a boolean value that indicates the user’s choice.

      Specifically, when the user closes the window or clicks on either the OK or Cancel button in the dialog box, the confirm method will return true if the user clicked on OK, and false if the user clicked on Cancel or closed the window.

      So, the correct answer is: It depends on the option selected by the user.

      Here’s an example to demonstrate the usage of the confirm method:

      let result = confirm("Are you sure you want to proceed?");
console.log(result);

      In this example, a confirm dialog box with the message “Are you sure you want to proceed?” is displayed. If the user clicks on OK, the value of result will be true. If the user clicks on Cancel or closes the window, the value of result will be false. The output will reflect the user’s choice.

      Therefore, the return value of the confirm method depends on the option selected by the user.

  12. The string "12" has been written into the str variable: (let str = "12";). Then the operations str = +str is performed. As a result, the variable str will contain:

    • NaN
    • 12
    • "+12"
    • "12"
    • Answers Explanation & Hints:

      The variable str will contain the number 12 as a result of the operation str = +str.

      Let’s break down the code step by step:

      1. Initially, the string “12” is assigned to the variable str using let str = "12";.
      2. The unary plus operator (+) is used to convert the string value to a number. When applied to a string, the unary plus operator attempts to convert the string to a numeric value.
      3. In this case, the unary plus operator is applied to the string “12”, resulting in the number 12.
      4. The result of the conversion is then assigned back to the variable str using str = +str. Since the conversion is successful, the variable str now holds the number 12.

      To illustrate this in code:

      let str = "12";
str = +str;
console.log(str); // Output: 12

      After executing the code snippet, the variable str will contain the number 12.

      So, the correct answer is 12.

  13. Analyze the code snippet:

    let nr = "1";
let x = (nr === 1);
let y = (nr == 1);
let z = (nr = 1);

    After its execution, the variables x, y, and z will have the values:

    • x: false, y: true, z: 1
    • x: null, y: null, z: 1
    • x: true, y: false, z:1
    • x: 1, y: 1, z: 1
    • Answers Explanation & Hints:

      After executing the code snippet:

      let nr = "1";
let x = (nr === 1);
let y = (nr == 1);
let z = (nr = 1);

      The variables x, y, and z will have the following values:

      • x will have a value of false.
      • y will have a value of true.
      • z will have a value of 1.

      Let’s break down the code snippet step by step:

      1. The variable nr is assigned the string value "1".
      2. The variable x is assigned the result of the comparison nr === 1. Since nr is a string and 1 is a number, the strict equality operator (===) compares both the value and the type. In this case, the types are different, so the result is false.
      3. The variable y is assigned the result of the comparison nr == 1. The loose equality operator (==) performs type coercion, trying to convert the operands to a common type before comparing. In this case, the string "1" is coerced to the number 1, resulting in a true comparison.
      4. The variable z is assigned the value 1. However, it’s important to note that the expression (nr = 1) is an assignment operation. It assigns the value 1 to the variable nr and also evaluates to the assigned value. Therefore, nr is updated to 1, and z is assigned the value of nr, which is 1.

      To summarize:

      • x has a value of false.
      • y has a value of true.
      • z has a value of 1.

      To illustrate this in code:

      let nr = "1";
let x = (nr === 1);
let y = (nr == 1);
let z = (nr = 1);

console.log(x); // Output: false
console.log(y); // Output: true
console.log(z); // Output: 1

      So, the correct answer is:

      x: false, y: true, z: 1

  14. The methods window.altert, window.confirm, and window.prompt are methods of the window object. Which of the following is not true?

    • The alert, confrim, and prompt methods require an argument specifying the position of the dialog in which the information will be displayed.
    • The alert, confirm, and prompt methods display information in modal windows that block access to the page until they are closed.
    • You can call window methods, such as window.alert, without including the name window, so calling alert("abc") would be correct.
    • The window object represents the window in which the HTML document containing the JavaScript code currently being executed is open.
    • Answers Explanation & Hints:

      The statement “The alert, confirm, and prompt methods require an argument specifying the position of the dialog in which the information will be displayed” is not true.

      The position of the dialog in which the information will be displayed is not specified as an argument when using the alert, confirm, or prompt methods. These methods display modal dialog boxes that are centered on the user’s screen by default. The position of the dialog is handled by the browser itself, and the methods do not provide a way to control or specify the position explicitly.

      The correct information regarding the given options is as follows:

      • The alert, confirm, and prompt methods display information in modal windows that block access to the page until they are closed. This means that the user needs to interact with the dialog before continuing to use the page.
      • You can call window methods, such as window.alert, without including the name window. For example, calling alert("abc") directly is correct. This is because these methods are part of the window object, and they can be accessed globally without explicitly referencing the window object.
      • The window object represents the window in which the HTML document containing the JavaScript code is open. It provides access to various properties and methods related to the window and the document within it.

      So, the statement “The alert, confirm, and prompt methods require an argument specifying the position of the dialog in which the information will be displayed” is not true.
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