A student holds a 2.0 kg air rifle, un-braced with a very loose grip. The muzzle velocity of a 2.0 g bullet fired from the rifle is about 140 m/s. What is the recoil speed of the gun? What could the student do to reduce the recoil speed of the air rifle? Explain.​

The answer is as follows in the photo

The boat's velocity relative to the riverbank can be resolved into two components. the component going north is 2.7 m/s and the component going west is 1.2 m/s.we add these two vectors and then find the magnitude of the resultant to get the speed.the magnitude of the resultant vector from adding can be obtained by the pythagorean theorem.    to two significant figures, the boat's speed relative to the riverbank is 3.0 m/s.