evaluating functions

For some reason I can't get these 3 problems correct:

g(x) = x^2(x-5)

g(3/2)
g(c)
g(t+2)

Any help would be greatly appreciated.
I contribute as much as I can and I don't seem to get any help. Maybe these are too hard of problems?

I will do one, and check you on the others.

g(t+2)=(t+2)^2 *(t+2-5)
= (t^2+2t+4)(t-3)
= (t^3+2t^2 + 4t -3t^2-6t-12)
then combine like terms.

Can you tell me if the correct answer for this is

t^3 -1t^2 -2t -12

correct

it's telling me that this answer is wrong.

for
g(c) i got c^3-5c
and for
g(3/2) i got -13.something and -8
but it keeps telling me i'm wrong

(it means my online class where i am working through these. however, i am not just asking you for answers, i have been sitting here on a friday night trying really hard to learn this and not getting this section...)

isnt g(c)=c^3-5c^2 ?

g(3/2)=((3 / 2)^2) * ((3 / 2) - 5)

= -7.87500

can you tell me why it's 5c^2 and not 5c?

f*x)=x^2-5x^2