What is the volume of a hemisphere with a diameter of 5.5 cm, rounded to the nearest tenth of a cubic centimeter?
The radius of the hemisphere is half of the diameter, which is 5.5 cm / 2 = <<5.5/2=2.75>>2.75 cm.
The volume of a hemisphere is given by the formula (2/3) * π * (radius^3).
So the volume of this hemisphere is (2/3) * π * (2.75^3) = 22.36 cubic centimeters.
Rounded to the nearest tenth of a cubic centimeter, the volume is 22.4 cubic centimeters. Answer: \boxed{22.4}.