Sabrina babysits for young kids in her neighborhood. Last Friday night, she babysat one child for 2 hours and made $16. Tonight, she babysat one child for 6.5 hours and made $34. Determine and interpret the rate of change and initial value.

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).