Usain Bolt, the fastest man in the world, stands at the beginning of an infinite flight of stairs, waiting for a nearby cannon to shoot a tennis ball straight up into the air. If he can climb one flight of stairs every 3 seconds, each of which is 10m tall, and the cannon shoots the tennis ball with an initial velocity of 250m/s:
A. How many flights of stairs can he climb before he'll need to lean out the window to catch the ball?
B. What will the speed of the ball be when he catches it?