Emma drank three 8 ounce cups of coffee. each cup of coffee contains 130 mg of caffeine. emma's body elimantes 13% of the caffeine each hour. write an exponential function that represents the amount of caffeine, c , in her body after t hours.

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).