web题库（选择题 判断题）

<script  type="text/JavaScript"＞

var a="RUNOOB-GOOGLE";

var x=a.lastIndexOf("G");

document.write(x);

</script＞

<script＞

var a = "RunoobGoogle";

var result = a.substring(4, 5);

document.write(result);

</script＞

<script＞

var val = 'www.example.com';

console.log(typeof val);

val = 10;

console.log(typeof val);

</script＞