1.sum 5 and   '5' ?

2.DataType Number?

3.callback a method or function?

4. Which method a create new Array ?

5.if method indexOf nothing find?

6.frist verson javascritp in a few days ?

7.this is a model function ()=>{} ?

8.in an object,when we use a function, it is a method or function ?

9.Which varaible a create ES6 ?

10.Method Super() For Which is Used Parent Class Or Child Class ?