A cannon shoots a 40 kg ball at a sailing ship and when it hits the wall of the vessel it applies 2000N of force. How much was it decelerated? PLS HELP

Mary starts from her house, walks 80 meters south, and stops to chat with her aunt on the sidewalk. after chatting for a few minutes, she walks 125 meters to the west to meet a friend and then walks 45 meters north with her friend to a cafe for lunch. overall, she takes 10 minutes to do all this. what is mary’s average speed?