Answer:
a = 8
r = 15%
When t = 3, y= 4.9
Explanation:
8 represents the original amount because that's what you're increasing, so a=8.
To find your percentage, look into the parenthesis to see the decimal. We see that it's 0.15, but that's not a percentage yet, so you have to multiply it by 100. Or, moving your decimal two times to the right. Therefore, r=15%.
Now to find what the function will equal when t=3, simply plug 3 for t. I've always used a calculator for this so I'm not going to write it out (sorry). Your result should be 4.9 (this is already rounded to the nearest tenth for you).