Answer:
D. 16 times.
Step-by-step explanation:
Volume of a cylinder = π r^2 h
π r^2 h = 432
Now if the diameter is reduced by 1/4 then the radius is reduced by a fourth also.
Let the new height be H, then:
432 = π (r/4)^2 H
so π r^2 h = π(r/4)^2 H
r^2 h = r^2 H / 16
h = H/16
H = 16h.