1.R varies jointly as the square of both x and y and inversely with cube of z.
2.R varies directly as the square of t and inversely as the cube of v.
3.P varies directly as the square of n and inversely as the square of d.
4.P varies directly with s and inversely with the square root q.
5.X varies directly as y and inversely as the square of z.
6.E varies jointly as square of L and cube root of Y.
