If you keep the radius the same and double the height, you find that by experimentation with this a few times, doubles your volume as well. That means that instead of 1/3 pi r^2 h, we will have 2/3 pi r^2 h. Your answer B.
Answer:

Step-by-step explanation:
see the attached figure to better understand the problem
we know that
----> by angle addition postulate
substitute the given values
