Question

What's the answer witch ones r composite 14 15
16 17 18 19
20
21

Answer 1

A composite number is a number with more than 2 factors and 16, 18, 20, and 21 are composite.

Answer 2

14 and 15 are also composite:

14 - 1×14, 2×7
15 - 1×15, 3×5

the first person probably didn't see the first row of numbers