Alan is connecting three garden hoses to make one longer hose. The green hose is 6.25 feel long the orange hose is 5.755 feet long and the black hose is 6.5 feet long how long will the new longer hose be? What operation will you use to answer this question

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).