College algebra NEED HELP!

[daisia99]

The number N of cars produced at a certain factory in 1 day after t hours of operation is given by N(t)=600t-15t^2, 0 _< t _< 10. If the cost C (in dollars) of producing N cars is C(N)=45,000+6000N, find the cost C as a function of the time of operation of the factory.

What is the cost C as a function of the time t of operation of the factory?

C(t)=?

 

[tkhunny]

N is a function of t, N(t)
As given, C is a function of N, C(N).
Perhaps C(N(t)) will get us somewhere?

 

[ag_roque]

C(t)=45,000+6000(600t - 15t²)
C(t) = 45000 + 3,600,000t - 90,000t²