Quiz: Functions, Arrays and Objects

5 questionsNo time limitPass: 60%+10 XP on first pass

Write functions and arrow functions, use the array methods every developer uses (map, filter, reduce, find, sort), work with objects, destructuring, spread and JSON.

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Question 1

What does this print?

console.log([1, 2, 3, 4].filter((n) => n % 2 === 0).map((n) => n * 10));

[ 10, 30 ][ 20, 40 ][ 10, 20, 30, 40 ][ 2, 4 ]

Question 2
What does this print?
```
console.log([5, 1, 10].sort());
```
[ 1, 5, 10 ][ 1, 10, 5 ][ 10, 5, 1 ][ 5, 1, 10 ]

Question 3

What does this print?

console.log([3, 4, 5].reduce((acc, n) => acc + n, 10));

122260345

Question 4
What does const { a, ...others } = { a: 1, b: 2, c: 3 } put in others?
[2, 3]{ b: 2, c: 3 }2undefined
Question 5
Which method returns the FIRST matching element (or undefined)?
filterfindmapsome