A boat is rowed perpendicular to the shore of a river that flows at 3.0 m/s as shown in the figure. The velocity of the boat is 4.0 m/s relative to the water. What is the magnitude of the
velocity of your boat relative to the shore?

A-5 m/s
B-10 m/s
C-15 m/s
D-20 m/s

During a medieval siege of a castle, the attacking army uses a trebuchet to hurl heavy stones at the castle walls. if the trebuchet launches the stones with a velocity of at an angle of 50.0°, (a) how long does it take the stone to hit the ground? (b) what is the maximum distance that the trebuchet can be from the castle wall to be in range? (c) how high will the stones go? show all your work.