Javascript Quiz For Intermediates

What is the output of the following code?

function foo() {
let x = 10;
function bar() { console.log(x); }
return bar;
}
let closureFunc = foo();
closureFunc();

Which array method in JavaScript creates a new array with the results of calling a provided function on every element in the calling array?

What is the purpose of the `bind()` method in JavaScript?

What will be the output of the following code?

const arr = [1, 2, 3, 4, 5];
const result = arr.reduce((acc, curr) => acc + curr, 10);
console.log(result);

Which keyword is used to declare a block-scope variable in JavaScript?

What does the `use strict` directive do in JavaScript?

Which of the following is NOT a valid way to create a new object in JavaScript?

What is the purpose of the `Promise` object in JavaScript?

How can you clone an array `sourceArray` into a new array `targetArray` in JavaScript?

Which event listener can be used to detect when an HTML form element loses focus (i.e. the user clicks outside the element or tabs away)?