State the possible number of positive real zeros, negative real zeros, and imaginary zeros of each function.

p(x) = x^5 - 6x^4 - 3x^3 + 7x^2 - 8x + 1

h(x) = 4x^3 - 6x^2 + 8x - 5

f(x) = x^3 - 6x^2 + 1

I would really love to find out how to solve these problems step by step.