mike is driving a boat west on a river at a water speed of 8.9  meters per second (m/s). The river current is flowing east at 3.2 m/s. A friend of john's is sitting in the back of the boat and throws a ball to the front with a speed of 12.4 m/s relative to the boat. What is the speed of the ball relative to the shore?

julia and alno are passengers on a train traveling at 5.7 meters per second (m/s) relative to the ground. mike is sitting facing alno, with her back to the front of the train. julia throws a ball to alno while the train is passing by a platform at a train station. To a person standing on the train station platform, the speed of the ball is traveling at an average speed of 2.2 m/s in the same direction as the train. Relative to the train, what speed is the ball is being thrown?

After traveling a distance of 30 meters (m) in 8 seconds (sec) at a constant speed, christy sees a truck starting to cross in front of her. She accelerates to a stop at a rate of -1.88 meters per second squared (m/s2). How much time does it take christy to stop? Answer to the nearest whole number.

ted has just completed 4 warm-up laps around a circular track that is 2,950  meter (m) long. he drove his race car at a constant speed for 2,050 seconds (sec). At the completion of the warm-up laps he arrives at the starting line. ted then increases his speed at a rate of 3.1 meters per second squared (m/s2). What is his speed after 17 seconds?

jow lifts a 150 Newton (N) box at constant speed. What is the reaction force to the weight of the box?