下面代码的输出是什么?const shape = { radius: 10, diameter() { return this.radius * 2; }, perimeter: () = 2 * Math.PI * this.radius};shape.diameter();shape.perimeter();
20 and 62.83185307179586
20 and NaN
20 and 63
NaN and 63
哪个选项是不正确的?const bird = { size: small};const mouse = { name: Mickey, small: true};
mouse.bird.size
mouse[bird.size]
mouse[bird[size]]
All of them are valid