Graphing questions are more difficult to answer without uploading images.You could use technology (a graphics calculator or graphics packages available on the Internet) to do the graphing for you.
Here's a graph using an Internet software (note the colour coding).You will notice that y=2.5^x (blue) grows faster that y=2.0^x (red), and that y=0.2^x (orange) decays faster than y=0.5^x (green).
The graphs show that they all pass through (0,1). After that, you will see that the blue line rises above the red line for x>0, meaning that 2.5^x grows faster than 2.0^x. Similarly, you will note that y=0.2^x (orange) goes below (for x>0) the curve for y=0.5^x (green), meaning that 0.2^x decays faster.