qiilee

A: Person {firstName: "Lydia", lastName: "Hallie"} and undefined B: Person {firstName: "Lydia", last

A: TypeError B: SyntaxError C: Lydia Hallie D: undefined undefined 参考答案：

```javascript let greeting greetign = {} // Typo! console.log(greetign) ``` - A: `{}` - B: `Referen

```javascript class Chameleon { static colorChange(newColor) { this.newColor = newColor re

A: Hello B: undefined C: ReferenceError D: TypeError 参考答案：

A: mouse.bird.size B: mouse[bird.size] C: mouse[bird["size"]] D: All of them are valid 参考答案：

A: 1 and false B: false and NaN C: false and false 参考答案：

A: 20 and 62.83185307179586 B: 20 and NaN C: 20 and 63 D: NaN and 63 参考答案：

```javascript for (var i = 0; i < 3; i++) { setTimeout(() => console.log(i), 1) } for (let i = 0;