19. A motorboat starts from rest (initial velocity v (0)=v sub 0=0). Its motor provides a constant acceleration of 4 ft/s^2, but water resistance causes a deceleration of v^2/400ft/s^2. Find v when t=10s, and also find the limiting velocity as t approaches +infinity(that is, the maximum possible speed of the boat).

Sorry for the alternate symbol, i have no italicized math symbols and infinity symbols, etc. Hope you understand so u can answer. Please, if someone knows the answer, please solve it coz i want to learn how to solve some problems for at least in differential equation.