Answer:
16
Explanation:
To solve this, we do the process of elimination.
First, let's consider all the numbers between 10 and 20.
11, 12, 13, 14, 15, 16, 17, 18, 19
Composite numbers are numbers that have factors other than 1 and itself. Prime numbers are numbers whose only factors are 1 and itself. Let's keep the composite numbers.
12, 14, 15, 16, 18
Let's keep the even numbers as well.
12, 14, 16, 18
Only one of these numbers is "square". I'm assuing this means that the square root of this number is a whole number. The only number that fits this criteria is 16.
16