Total surface area of a cylinder $= \dots$

Six wooden cubes of length $3 \, cm$ are arranged in a row touching each other face to face. Find the total surface area of the solid formed in this manner. (in $cm^2$)

The radius of a hemispherical dome of a temple is $21\, m$. Find the cost of painting its outer surface at the rate of ₹ $80/m^2$. (in ₹)

$A$ right triangle,whose sides are $3\, cm$ and $4\, cm$ (other than the hypotenuse) is made to revolve about its hypotenuse. Find the surface area of the double cone so formed. (Use $\pi = 3.14$) (in $cm^2$)

The surface area of a sphere is $\ldots \ldots$

The area of the base of a cylinder is equal to: