Find the surface area of a sphere of radius $50\, cm$ $(\pi = 3.14)$ (in $cm^2$).

Find the volume of a hemisphere with a diameter of $12 \, cm$. (Use $\pi = 3.14$) (in $cm^3$) (in $.16$)

Find the volume of a sphere with radius $2.1 \, m$ (in $m^{3}$).

The radii of two cylinders are in the ratio of $2:3$ and their heights are in the ratio of $5:3$. The ratio of their volumes is

Find the surface area of a sphere of diameter $49\, cm$ (in $cm^2$).

Write True or False and justify your answer.
$A$ right circular cylinder just encloses a sphere of radius $r$ as shown in the figure. The surface area of the sphere is equal to the curved surface area of the cylinder.