Core Concepts — Series 2

Preview — 3 of 10 questions

What is logged by the following code?

javascript
let str = "Hello";
str.toUpperCase();
console.log(str);
A"HELLO"
B"Hello"
Cundefined
DTypeError: Cannot read property

What does the following code log?

javascript
const arr = [1, 2, 3, 4, 5];
arr.length = 2;
console.log(arr);
A[1, 2]
B[1, 2, 3, 4, 5]
C[1, 2, undefined, undefined, undefined]
D[]

What is logged?

javascript
const a = 3, b = 4;
console.log(`Sum: ${a + b}`);
ASum: ${a + b}
BSum: NaN
CSum: 7
DSyntaxError

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