The diameter of a sphere is 4.24 m . Calculate its surface area with due regard to significant figures.

Explanation

Diameter d = 4 . 24 m
Radius r = `d/2 = (4.24)/2 = 2.12`
surface area of sphere `= 4 pi r^2 = 4xx 3.1428xx2.12xx2.12`
In the aboce multiplication 2.12 has 3 significant figures.
Hence 3.1428 is rounded off to have 3 + 1 = 4 significant figures. It becomes 3.143 .
Surface area `= 4 xx 3.143 x 2.12 xx2.12=56.50`
56.50 this to be rounded off to have 3 significant figures.
`therefore ` Area is 56.5