volume=height times area of base
area of base=circle=pi times r^2
subsitute
volume=392.5
height=5
subsitute
392.5=5 times pi times r^2
divide both sides by 5
78.5=pi times r^2
aprox pi to 3.14
78.5=3.14 times r^2
divide both sides by 3.14
25=r^2
square root both sides
5=r
A. Radius=5 in
surface area=2(area of base)+(circunfernce times height)
area of base=pi times r^2=3.14 times 5^2=78.5
circumference=2 times pi times r=2 times 3.14 times 5=31.4
height=5
surface area=2(78.5)+(31.4 times 5)
surface area=157+157
surface area=314
A. radius=5 cm
surface area= 314 cm^2