Question

Which number replaces the question mark?
please say answer with full explanation​

Answer 1

Answer:

15

Step-by-step explanation:

Hope it helps you

Answer 2

16

This is a chain of squaring the numbers from 1 to 9 starting from left bottom vertice

${1}^{2} = 1 \\ {2}^{2} = 4 \\ {3}^{2} = 9 \\ {4}^{2} = 16 \\ {5}^{2} = 25 \\ {6}^{2} = 36 \\ {7}^{2} = 49 \\ {8}^{2} = 64 \\ {9}^{2} = 81$