Cryptography problem

I can calculate AES all the way through and decrypt but I cannot do this question. Need urgent help due in less than 20 hours. in AES, Suppose the keys W(4), W(5), W(6) and W(7) are as follows: W(4) = W(6): 01100010 01100011 01100011 01100011 W(5) = W(7): 01100010 01100011 01100011 01100011 Find W(8)