The perimeter of one face of a cube is $20\, cm$. Its volume is.........$cm^3$

$A$ right-angled triangle having base $6.3 \, m$ and height $10 \, cm$ is rotated around its height. Find the volume of the cone thus formed. Also,find the curved surface area (in $m^2$). (in $.83$)

$A$ right circular cone is exactly fitted inside a cube in such a way that the edges of the base of the cone are touching the edges of one of the faces of the cube and the vertex is on the opposite face of the cube. If the volume of the cube is $343 \, c.c.$,then what approximately is the volume of the cone? (in $c.c.$)

The cross section of a canal is in the shape of an isosceles trapezium which is $4 \ m$ wide at the bottom and $5 \ m$ wide at the top. If the depth of the canal is $2 \ m$ and it is $120 \ m$ long,what is the maximum capacity of this canal? (in $m^3$)

The radii of a cylinder and a cone are equal. If the height of the cylinder is equal to the slant height of the cone,then the ratio of the curved surface areas of the cylinder and the cone is: (in $:1$)

$A$ right circular cylindrical tunnel of diameter $5\, m$ and length $10\, m$ is to be constructed from a sheet of iron. The area of iron sheet required will be..........$\pi\, m^2$.