Let $S$ be the value of a stock that evolves according to $dS$=$\mu$$Sdt$ + $\sigma$$SdB$. A contract has a payoff at expiration of $V_T$=$(S_T)^3$. What is the value of $V_0$ of the contract at $t=0$?
Express your answer in terms of $r, T, \sigma, \mu$ and $S_0$
I tried to tackle this problem using Ito's Lemma but it doesn't seem to give me the right answer. Is there any way I can use $r$ as the risk-neutral rate?