Calculating Big O estimates. Please refer to the following picture.

Find the simplest Big O estimate for the following functions f(n) = 5n^2 - 2n^2 - n + 2 g(n) = (n/10 + 30) (2n - 600) h (n) = (4n - 2)(log (5n + 3)) r(n) = (squarerooot n + 20log2(n) + n/2) (4n + log n + 5)