Answer 1

• In JavaScript, a number can be a primitive value (typeof = number) or an object (typeof = object).

The valueOf() method is used internally in JavaScript to convert Number objects to primitive values.

There is no reason to use it in your code.

• The value property sets or returns the contents of elements like:

input elements, text area elements, output elements, select elements and option elements.

Example codes:
https://code.sololearn.com/W4yXm86zeI5p/?ref=app
https://code.sololearn.com/W6mF9Q5ibTrt/?ref=app