The answer can either be 1.25 or 2. As long as the value of A is greater than 1, the function is an exponential growth function.
B): x=8, y=8root2, z=16
c): x=4, y=12, z=8root3
The ones later one you can do by your self.
30 60 90 triangle side ratio: 1:root3:2
90 45 45 triangle side ratio: 1:1:root2
Based on limited information, it can only be inferred that angle give is either 160 degrees or 20 degrees.