For the following questions answer them individually
A drum of kerosene is $$\frac{3}{4}$$ full. When 30 litres of kerosene is drawn from it, it remains $$\frac{1}{2}$$Â full. The capacity of the drum is
If a and b are two odd positive integers, by which of the following integers is $$(a^4-b^4)$$ always divisible ?