For the following questions answer them individually
A cylinder and a cone have equal radii of their bases and equal heights. If their curved surface areas are in the ratio 8 : 5, the ratio of their radius and height is
A solid is hemispherical at the bottom and conical above. If the surface areas of the two parts are equal, then the ratio of radius and height of its conical part is
Base of a right prism is an equilateral triangle of side 6 cm. If the volume of the prism is 108 $$\sqrt{3}$$cc. its height is
The value of k for which the graph of (k -1) x + y - 2 = 0 and (2 - k) x - 3y + 1) = 0 are parallel is
The length of a shadow of a vertical tower is $$ \frac{1}{\sqrt3} $$Â times its height. The angle of elevation of the Sun is
If a, b, c are three non-zero real numbers such that a + b + c = 0, and b2 ca, then the value of is $$\frac{a^{2}+b^{2}+a^{2}}{b^{2}-ca} is $$
If $$a^{4}+ a^{2}b ^{2}+ b^{4}$$ =8 and $$a^{2}+ ab+ b^{2}$$ = 4, then the value of ab is
