How would you use the binomial theorem to expand and simplify (2x^2 - 4x + 7)^3. I haven't done a question like this before.. I need helpp thankss

In the binomial expansion of (a+b)^12 determine A) the value of k in the term containing a^2k b^k B) the coefficient of that term, first in c(n,r) form, and then evaluate C) the number of terms in the expansion D) the middle term I don't understand This is from my statistics/ data...