Expert Mastery

Preview — 3 of 10 questions

What is the output of the following code?

javascript

console.log("Start");
setTimeout(() => console.log("Timeout"), 0);
Promise.resolve().then(() => console.log("Promise"));
console.log("End");

AStart → Timeout → Promise → End

BStart → End → Promise → Timeout

CStart → Promise → End → Timeout

DStart → Timeout → End → Promise

What will be logged to the console?

javascript

function createCounter() {
  let count = 0;
  return () => console.log(++count);
}

const counter1 = createCounter();
counter1();
counter1();

A1, 1

B1, 2

Cundefined, undefined

DReferenceError

What is the output?

javascript

const obj = {
  value: 10,
  getValue: () => console.log(this.value)
};

obj.getValue();

A10

Bundefined

CError

Dnull

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