A near-sighted person has a far point of 75cm. That person gets corrective glasses, which rest 2cm from their eyes, in order to give them a normal far point that is infinitely far away. However, those corrective lenses don't just change the person's far point. While wearing their glasses, what is this person's new near point (assume that without glasses, their near point is the normal 25cm)

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.