Answer:
m^8a+8m^6a+24m^4a+32m^2a+16
Explanation:
Simple binomial theorem.
(x+y)n = nC0 xny0 + nC1 xn-1y1 + nC2 xn-2 y2 + ... + nCn-1 x1yn-1 + nCn x0yn
OR
(x+y)n = ∑nk=0nCk xn-kyk = ∑nk=0nCk xkyn-k
plugging the numbers into this theorem yields that answer.