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Mariulka [41]
3 years ago
8

The surface area of a sphere is found using the formula SA=4πr^2, where r is the radius. If the surface area of a sphere is 64π

square feet, what is the radius, in feet? A. 3 B. 18 C. 1 D. 4
Mathematics
2 answers:
Setler79 [48]3 years ago
6 0
The answer should be d
64pi=4pir^2
cancel the pi
64=4r^2
16=r^2
r=4
masha68 [24]3 years ago
5 0
SA =  4 \pi  r^{2}
64 \pi = 4 \pi r^{2}
16= r^{2}
r^{2}=16
 r=4
 (Answer D)

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Step-by-step explanation:

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               \frac{X -  \mu }{\sigma }  =  Z (The \  standardized \  value \ of  \  X )

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=>    P(350 <  X  650 ) =  0.93319 -  0.066807

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