Question 1

Unpack (extract values from arrays/objects)

Accepted Answer

Destructuring

Question 2

Modify (transform every element)

Accepted Answer

map()

Question 3

Find (keep only matching elements)

Accepted Answer

filter()

Question 4

Reduce (combine everything into one value, like sum, max, min, or average)

Accepted Answer

reduce()

Question 5

The type of destructuring where values are extracted based on their index position.

Accepted Answer

Array Destructuring

Question 6

The type of destructuring where values are extracted using property names.

Accepted Answer

Object Destructuring

Question 7

The symbol used to skip an item in array destructuring.

Accepted Answer

Comma

Question 8

The operator used to collect the remaining elements in an array.

Accepted Answer

Rest Operator

Question 9

The value assigned when a destructured variable is undefined.

Accepted Answer

Default Value

Question 10

The process of giving a destructured object property a different variable name.

Accepted Answer

Renaming Variables

Question 11

Destructuring can also be performed inside a function's ________.

Accepted Answer

Parameters

Question 12

In array destructuring, variables correspond to the array's ________.

Accepted Answer

Index

Question 13

A function that accepts another function as an argument or returns a function.

Accepted Answer

Higher-Order Function

Question 14

These functions allow programmers to focus on the "what" rather than the "how."

Accepted Answer

Higher-Order Functions

Question 15

The array method that transforms every element into a new array.

Accepted Answer

map()

Question 16

The method that does not modify the original array while transforming its elements.

Accepted Answer

map()

Question 17

The method commonly used to double every number in an array.

Accepted Answer

map()

Question 18

The function often written using the => syntax in the examples.

Accepted Answer

Arrow Function

Question 19

The array method that does not execute its callback for empty elements while transforming values.

Accepted Answer

map()

Question 20

The array method that creates a new array containing only elements that pass a test.

Accepted Answer

filter()

Question 21

The function used in the presentation to determine if an age is 18 or older.

Accepted Answer

checkAdult

Question 22

The array method used to extract only even numbers.

Accepted Answer

filter()

Question 23

The array method used to retrieve records where firstName == Chiz.

Accepted Answer

filter()

Question 24

The array method that returns only elements satisfying a condition.

Accepted Answer

filter()

Question 25

The array method that reduces all elements into a single value.

Accepted Answer

reduce()

Question 26

The variable that stores the accumulated result in reduce().

Accepted Answer

Accumulator

Question 27

The value supplied as the starting value of the accumulator.

Accepted Answer

Initial Value

Question 28

The method used to compute the sum of all elements in an array.

Accepted Answer

reduce()

Question 29

According to the presentation, this method can also find the highest value in an array.

Accepted Answer

reduce()

Question 30

The method used when you want to transform every element in an array.

Accepted Answer

map()

Question 31

The method used when you want to obtain only the required values based on a condition.
Answer: filter()

Accepted Answer

filter()

Question 32

The method used to reduce an array into a single value such as sum, maximum, minimum, or average.

Accepted Answer

reduce()

Question 33

What will be the value of num1?
const numbers = [10, 20];
const [num1, num2] = numbers;

Accepted Answer

10

Question 34

What will be the value of num2?
const numbers = [10, 20];
const [num1, num2] = numbers;

Accepted Answer

20

Question 35

What is the output of third?
const colors = ["Red", "Green", "Blue"];
const [first, , third] = colors;

Accepted Answer

Blue

Question 36

What is stored inside rest?
const numbers = [1,2,3,4,5];
const [first, ...rest] = numbers;

Accepted Answer

2,3,4,5

Question 37

What will be the value of age?
const user = {
    name: "John"
};

const {name, age = 18} = user;

Accepted Answer

18

Question 38

. What is the value of num1?
const numbers = {
    a: 5,
    b: 10
};

const {a: num1, b: num2} = numbers;

Accepted Answer

5

Question 39

What JavaScript feature is used in the code below?
const {name, age} = person;

Accepted Answer

Object Destructuring

Question 40

What JavaScript feature is used in the code below?
const [x, y] = numbers;

Accepted Answer

Array Destructuring

Question 41

What method is used in this code?
const doubled = numbers.map(num => num * 2);

Accepted Answer

map()

Question 42

What is the output?
const numbers = [1,2,3];
const doubled = numbers.map(num => num * 2);

Accepted Answer

2,4,6

Question 43

Which function syntax is used here?
num => num * 2

Accepted Answer

Arrow Function

Question 44

What happens to the original array after using .map()?
const doubled = numbers.map(num => num * 2);

Accepted Answer

remains unchanged.

Question 45

What method is used in this code?
const adults = ages.filter(age => age >= 18);

Accepted Answer

filter()

Question 46

What is the output?
const ages = [12,18,20,15];
const adults = ages.filter(age => age >= 18);

Accepted Answer

[18,20]

Question 47

What condition is being tested?
age >= 18

Accepted Answer

Age is greater than or equal to 18.

Question 48

What method is used in this code?
const sum = numbers.reduce((acc, num) => acc + num, 0);

Accepted Answer

reduce()

Question 49

What is the output?
const numbers = [1,2,3,4];
const sum = numbers.reduce((acc, num) => acc + num, 0);

Accepted Answer

10

Question 50

What is the initial value of the accumulator?
numbers.reduce((acc, num) => acc + num, 0);

Accepted Answer

0

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SYSINTEG - L1