From question, I guess the inputs should be velocity and depth of the container. The outputs should be time taken to reach the required velocity (t1) and time taken to reach the bottom of the container (time). I have created the function Velo_ball(velocity,depth) which inputs the velocity and depth as input and gives the output t1=time at which given velocity is acheived and time= time to hit the bottom of container. Hope this helps. If not please rectify.