$1\,m^3 = \dots \dots \dots cm^3$.

$A$ canal is $300 \,cm$ wide and $120 \,cm$ deep. The water in the canal is flowing with a speed of $20 \,km/h$. How much area will it irrigate in $20 \,minutes$ if $8 \,cm$ of standing water is desired? (in $hectares$)

How many spherical lead shots,each of diameter $4.2 \, cm$,can be obtained from a solid rectangular lead piece with dimensions $66 \, cm \times 42 \, cm \times 21 \, cm$?

$A$ metallic spherical shell of internal and external diameters $4 \, cm$ and $8 \, cm$,respectively,is melted and recast into the form of a cone of base diameter $8 \, cm$. The height of the cone is (in $cm$):

The volume of a cylinder is $550 \, cm^{3}$ and its radius is $5 \, cm$. Then,the height of the cylinder is $\ldots \ldots \ldots \, cm$.

If the radius of a sphere is doubled,its volume becomes $\ldots \ldots \ldots$ times the volume of the original sphere.