How do I find f and q for v(t) = 1.5 + cos(2*pi*f*t + q) (v(t) is the envelope), while v(t) completes

exactly 2 periods while c(t) completes (exactly) 40

periods; and v(0) = 2.5 (maximum possible value).

From previous question, I got:

F=200;%%frequency T=1/F;%%period N=800;%%# of sampling d=50*T/N;%%stepside td = 0 : d : 50*T-d;%%discrete time axis

c = cos(2*pi*F*td);%%this is c(t)

figure(1);plot(td, c)

0.8 0.6 0.2 0.2 0.4 0.6 0.8 0.05 0.1 0.2 0.25 0.8 0.6 0.2 0.2 0.4 0.6 0.8 0.05 0.1 0.2 0.25