Determine if each of the following is "proper" or "improper" rational function.
f(x)=x3+3x2+77x2-2x+1
f(x)=x3-5x2-4
f(x)=3x2-2x+7x5-5
f(x)=x3+4x2+2x10x+7
f(x)=5x2-4x+47x5-2x+3