Ihave no idea how to simplify fractions.

Alright lets start by defining both prime and composite.

A natural number that has exactly two factors, one and itself, is called a prime number.
And natural number, other than one, that is not prime, is composite.

So lets start on #1: 8. We should know right off the bat that this is an even number and therefore can be divided by 2 (8/2=4). Since 8 is not one, we know that it is a composite number.

On #2 the number is 13. Now try some random numbers (2,3...) and you will find that nothing will give you a whole number (other than one). This means this number is prime.

#3 is the number 24 which is also even and can be divided by two, therefore is it composite.

33 is the number on #4. Now this one you should look at and realize that it can be divided by 11. Any two numbers that are the same (11, 22, 33, 44, 55...) can be divided by 11. This number is composite.

#5, the last one, is number 89. 89 is not a composite number, because it's only divisors are one and itself. This would make is a prime number.

Sorry this was kinda long, but I hope it helps! If you have any questions, feel free to ask!