Can you explain how to solve such type of statistics questions?

It would be great help if you can explain variation of such questions as well.

The random variable X has the following probability density function: fx (x) = 10 elsewhere. Find E(X) and Var(X). Select one: O E(X) = 2, var(X) = 3 O E(X) = 3, Var(X) = 9 O E(X) = 2/3, Var(X) = 2/9 O E(X) = 3, Var(X) = 3The random variable X has the following probability density function: fx (I) = Je- -00