Answer:
Exact volume = 30,000 + 5,000pi cubic mm
Approximate volume = 45,700 cubic mm
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Step-by-step explanation:
Break the figure into two pieces.
The top part is a half-cylinder with radius r = 20/2 = 10 mm and height h = 100 mm.
The volume of this half-cylinder is
V = 0.5*(full cylinder volume)
V = 0.5*pi*r^2*h
V = 0.5*pi*10^2*100
V = 5000pi
This is exact in terms of pi.
The lower part is a 20 mm by 100 mm by 15 mm rectangular block. It has volume of length*width*height = 20*100*15 = 30,000 cubic mm.
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We'll add the two volumes found earlier to get the overall volume.
The total exact volume is 30,000+5,000pi cubic mm.
To get an approximation, you can use something like pi = 3.14
30000+5000pi = 30000+5000*3.14 = 45,700 cubic mm is the approximate volume when using pi = 3.14