Bernoulli process, expected value of conditional

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Consider a Bernoulli process where at each step or time there is a success, 1, or failure, 0. $N_k$ denotes the number of successes at the $k^{th}$ step. The probability of success is $p$ and the probability of failure is $q$, where $p + q = 1$.

The problem is to find $$E[3N_5^4 + N_8^3 | N_0, N_1, N_2]$$

I don't understand the problem. I thought that past N have no influence on future N.

I know that $E(N_n) = np$ and $E(N_n^2) = n^2p^2 + npq$, but I don't know how to tackle those greater exponentials.

EDIT:

The problem was actually to show that $$E[3N_5^4 + N_8^3 | N_0, N_1, N_2] = E[3N_5^4 + N_8^3 | N_2]$$