(1 point) A water balloon of mass 170 grams is launched with an initial (vertical) velocity of 15 meters per second, and is leaking at a rate of 35 grams per second. Assume air resistance is proportional to velocity with coefficient ke-46 grams per second, and use 9.81 meters per second squared for the acceleration due to gravity D du Using the differential equation m mg-ku, find the velocity of the balloon as a function of time dt v(t)