Answer: about 16.75 cubic inches
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Step-by-step explanation:
d = 4 is the diameter
r = d/2 = 4/2 = 2 is the radius
Let's calculate the volume of a full sphere of radius r = 2
The result is approximate since 4/3 doesn't produce a nice decimal value (it produces 1.333 with the 3s repeating); also because pi = 3.14 is approximate.
The result 33.4933333 represents a full sphere volume, but we want half a sphere (aka hemisphere)
We'll divide it in half to get (33.4933333)/2 = 16.74666665 which rounds to about 16.75 cubic inches
Round each value according to the instructions your teacher provides.