Wile E. Coyote is so desperate to catch the Roadrunner that he builds himself a catapult to use on those darn vertical cliffs he is always running into. He figures he will need it to shoot him
Notice that the question is asking, 'how fast?'.
Be mindful of units.
Use the eTool below to visualize the problem.
Click the link at right for the full version of the eTool: Calc 6-139 HW eTool