Elena’s father puts $460 into savings account for her. the pays 2.5% simple interest each year. if he neither adds nor withdraws money from the account, how much interest will the account earn after 4years?
round to the nearest cent

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).