Answer:
r = 44
Step-by-step explanation:
12 = r - (34 - 2)
Solve for r
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To solve, we need to isolate r.
Distribute the negative sign with the numbers within the parenthesis :
12 = r - 34 + 2
Add like terms :
12 = r - 32
Add 32 to both sides :
44 = r
r = 44
Cone's volume is third of cylinder's volume, so 321*1/3=107 cubic units. Answer A. is correct.