Answer:
8 in³
Explanation:
Volume of a sphere is:
V = ⁴/₃ πr³
Volume of a hemisphere is half of that:
V = ⅔ πr³
Volume of a cone is:
V = ⅓ πr²h
The height of the cone is equal to the diameter, so h = 2r.
V = ⅓ πr²(2r)
V = ⅔ πr³
The hemisphere and cone have the same radius, so they have the same volume. So the total volume is 4 in³ + 4 in³ = 8 in³.