16. You add 13 to 35 which makes 3y=48. Then to get y by itself you have to divide both sides by 3. 48/3=16.
H=1in
You would need to use the equation V= pie times radius squared times height. Since it gives you the diameter, you would need to divide 3 by 2 to get 1.5. So now you would plug in 7.1=pie×1.5(squared)×h
Now solve the equation to get 1in.
And you can check this answer by using this same equation to plug in pi×1.5 (squared)×1 and you will get 7.1 as your volume.