The volume of a sphere of radius `r` is obtained by multiplying its surface area by `4/3` (b) `r/3` (c) `(4r)/3` (d) `3r`

The volume of a sphere of radius 'r' is obtained by multipying its surface area by

The curved surface area of a right circular cylinder of base radius r is obtained by multiplying its volume by 2r(b)(2)/(r) (c) 2r^(2) (d) (2)/(r^(2))

The total surface area of a hemisphere of radius r is pir^2 (b) 2pir^2 (c) 3pir^2 (d) 4pir^2

The total surface area of a hemisphere of radius r is pir^2 (b) 2pir^2 (c) 3pir^2 (d) 4pir^2

A sphere of maximum volume is cut out from a solid hemisphere of radius r. The ratio of the volume of the hemisphere to that of the cut out sphere is: (a) 3:2 (b) 4:1 (c) 4:3 (d) 7:4

The rate of change of surface area of a sphere of radius r when the radius is increasing at the rate of 2 cm/sec is proportional to: a) 1/r b) r c) 1/r^2 d) r^2

The rate of change of surface area of a sphere of radius r when the radius is increasing at the rate of 2 cm/sec is proportional to a)1/r b)1/r^2 c)r d)r^2