Find asymptotically tight bounds for the following functions:

-f(n) = summation from i=1 to n^4 of i^2

-f(n) = (n^2)log2(n^7n+1)

-f(n) = summation from i=1 to 25 of ((i^3)+(3^i))

-f(n) = (7n^3 + 3n^2 + 2n + 9)(9n^7 + 3n^5 + 2n +4)

-f(n) = 2^(n-1)