HRWP36p78

To solve this problem, you have to do a bunch of steps. I'm listing the steps to part a in reverse order since that is how you would need to tackle the problem:

1. To find d, you need the horizontal speed (v_x) since
   d = (v_x) t and t=4s.


2. To find v_x, you need the total velocity (v) when it lands on
   the roof (because v_x = v cos(60°))


3. To find v, you need to find the vertical velocity (v_y) when it
   lands on the roof.


4. To find the final vertical velocity (v_y), you need the initial
   vertical velocity (v_y0).


5. To find v_y0, use the acceleration equation:
   
   h = .5 g t² + v_y0 t


6. Now, you can find v_y since v_y = v_y0 + gt


7. Next, you can find v since v_y = v sin(60°)


8. Going backwards, you can find d.


9. Parts b and c are easy since you already have v_y0 and
   v_x (it's the usual translation from cartesian to polar coordinates).