2. What is your reasoning? First of all, what is your random variable $X$? Define that first. Then look at $E(X)$. There are $6$ outcomes. What is the probability of each outcome? You can also think about this as rolling a six-sided die.
3. It would be $6(1+\frac{1}{2}+\frac{1}{3}+\frac{1}{4}+\frac{1}{5 }+\frac{1}{6})$.