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Question

calculate the volume of a sphere daimeter 17cm.
b)evaluate the surface area of radius 8.5cm
c)calculate the volume and surface are of the surface earth assuming that it is a sphere of radius 6,370km,
correct to 3 significant figure ( use pi=3.142 ).

Answer 1

a) V= (4/3) * 3.142 * r^3
plug in r=17/2
2572.77 cm^3

b) S= 4 * 3.142 * r^2
plug in r=8.5
908.038 cm^2

c) plug in r=6370 in each of the above formulas

Answer 2

volume of sphere =4/3pir^3
=(4*3.142*(17/2)^3)/3
=(4*3.142*17^3)/8*3
=2 572.774cm^3

b)surface area = 4pir^2
=4*3.142*(8.5)^2
=908.038cm^2

c)volume of earth
=4/3*3.142*6370^3
=1.08283732 × 1012km^3

surface = 4.3.142*6370^2
=509 970 479km^2