13. Write and solve a system of equations for each story problem.
A class of 366 students went on a field trip. They took 12 vehicles, some vans and some buses
Find the number of vans and the number of buses they took if each van holds 6 students and each bus holds
55 students

Amass weighing 16 pounds stretches a spring 8/3 feet. the mass is initially released from rest from a point 2 feet below the equilibrium position, and the subsequent motion takes place in a medium that offers a damping force that is numerically equal to 1/2 the instantaneous velocity. find the equation of motion if the mass is driven by an external force equal to f(t)=cos(2t).