Trash scheduling model for AMPL

Question

I have been working on a grabage collection problem in AMPL and these are the data:

Variables

Schedule and Garbage Collected

Obj fun : minimize total operational costs

Constraints :

1. Each shift should not work for more that 8 hrs

2. The garbge collected per shift is not more than 500 tons

3. On sundays, only - 4 dump trucks - 7 compactor truck - 8 mini dump truck

Variables

Schedule and Garbage Collected

Can anyone help me with this problem and how it can be formulated? especially with the data? Thank you!