A top is of the shape of a cone over a hemisphere. The radius of the hemisphere is 3.5 cm. The total height of the top is 15.5 cm. Find the total area of the top.

214.5 cm2 21.45 cm2 215.4 cm2 21.43 cm2

214.5 cm2

Height of cone = 15.5 – 3.5 = 12 cm $l=\sqrt{h^2+r^2}$ $=\sqrt{(3.5)^2+(12)^2}=12.5cm$ C.S.A. = $πrl$ = 137.5 sq cm C.S.A. of hemisphere = $2πr^2=77cm^2$ ∴ Total area of the top = 214.5 sq. cm.