Can anyone help with these two? Thank you!

5) A 0.6-kg block starts from rest and slides down the ramp Block I seen in the gure. The initial height is y1 =2.10m and the 'l' 6 nal height is y2 = 0.90m. There is considerable friction y] m between the block and the ramp. If the speed of the block at the end of the ramp is only 3.2 m/s, how much energy was dissipated due to the work by friction? 6) A 85 kg bicyclist is driving at 5.5 m/s when his attention gets occupied by an event on the side of the path. Unfortunately, that makes him overlook a very low-growing tree branch that hits his head and brings him to a stop. If the time to bring him to a stop is about 0.060 3, what is the magnitude of the average net force with which the branch did hit him? (Do not worry about the mass of the bicycle and what motion it may do.)