. A tower is 42 metres high and stands on top of a hill. From a point some distance from the base of the hill, the angle of elevation to the top of the tower is 13.2°, and the angle of elevation to the bottom of the tower is 8.3°. Find the height of the hill.​

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).