2010 · Q79
A hemisphere is made of a sheet of a metal 1 cm thick. If the outer radius is 5 cm, what is the weight of the hemi- sphere.(1 cm3 of the metal weighs 9 g) ?
Elementary MathematicsMensuration
- A54π g
- B366π g
- C122 πg
- D108π g
Explanation
Volume=(2/3)π(125-64); weight=9×122π/3=366π g.