During the conversion of a solid from one shape to another,the volume of the new shape will

$A$ cylinder is closed at both the ends by hemispheres. The radius of the cylinder is $7 \, cm$ and the total height of the article is $34 \, cm$. Find the total surface area of the article. (in $cm^2$)

Two solid cones $A$ and $B$ are placed in a cylindrical tube as shown in the figure. The ratio of their capacities is $2:1$. Find the heights and capacities of the cones. Also,find the volume of the remaining portion of the cylinder (in $cm^{3}$).

The ratio of the diameters of two cylinders is $3:4$ and the ratio of their heights is $4:5$. Then,the ratio of their volumes is ..... .

The area of the base of a cone is $60 \, cm^{2}$ and its height is $15 \, cm$. Then,the volume of the cone is $\ldots \ldots \ldots \, cm^{3}$.

$A$ metallic sphere of radius $21 \,cm$ is melted and recast to form a wire with diameter $0.5 \,cm$. Find the length of the wire in $m$.