yes why?

why?

it is not a good practice adding regex to your code :D

The underlying expression of your statement is incorrect, because this function will be implemented into other code and so this function will be executed an unknown number of times per second. Always keep that in mind :) .

True,although it will only ever run over an array of 10.

a doesn't need you to type it, it's value is inferred

Were you trying to make this complicated?

You answer your question in javascript.
If you are testing coding knowledge then please remove all mention of how to solve the issue at hand (i.e the bit about %)

Some spelling mistakes on the word 'divided' spelt here as 'devided'.

Also, may want to add some tests and explanaition for non-whole numbers.
I know most people use 2 as their fail point but if you put 2.1 under your conditions this would be a prime number when it is c;early not.

This is a good choice. However for efficiency you should use square root of a.
This will require your code to pass through fewer iterations to find the correct answer.
However you will have to amend the end of your loop as i <= SQRT(a)

Not sure if there needs to be a kata for this.
I get you're going for easy but this seems to be teaching simple maths more than coding ability.

Make it into epoch seconds

It says the expected response to:
addWord(list, "hello")
should be ["hello"]
in the instructions

Your example test case is the wrong way round. Should be expected, actual