Question: How Can I label a multiple plot in one graph ?

Hi  Mapleprime community.
 
I would like to know, how can I  put a label for each in this procedure I write below. 
I need to  show  values for  the parameter q. If this possible ?¿
Here it is the procedure I already did.
restart;with(plots):
> M:= q^(1-q)*MM;
> N:= ( 1 - ( 1 - (N0/M)^(1-q))*exp(- q*t))^(1/(1-q));
> F:= subs(N0=0.65,q= 0.2,MM=25, N);
> G:= subs(N0=0.65,q= 0.5,MM=25, N);
> H:= subs(N0=0.65,q= 2/3,MM=25, N);
> P:= subs(N0=0.65,q= 4/3,MM=25, N);
> plot([F,G,H,P],t=0..20);
Please Wait...