Please answer questions

Problem 1 (3.0 pts.). A hiker walks with an average speed of V : 2.5131/3. (a) What distance in kilometeir's and in meters does the hiker travel in a time of t : 2 hours? (b) How much time did it take her to complete the 1st kilometer of her journey? Problem 2 (3.5 pts.). A ball is thrown upward with an initial velocity of V;- : lZ-m/s. Use the approximate value of gr : 10 urn/32 for your calculations. (e) What is the velocity of the ball t1 : LOseconds after it is thrown? (b) W'hat will be the location of the ball after t2 : 2.0 seconds compared to it initial position? Problem 3 (3.5 pts.). Two men are pushing a box of a mass Ital : 100 kg in opposite directions by applying forces F1 : 1300 N and F2 : 5003?, as is shown in Fig. 1 ((3.). There is also an unknown friction force f acting on the box. (0.) Find the friction force f if the box moves with acceleration a. : 0.5 Wt/32. (b) How will this acceleration change if another small box of mass m = 10 kg is placed on top of our box 1M, see Fig. l (3)). Assume that the friction force remains the same when the other box at is added. Will this acceleration increase or decrease and why? Figure 1: Schematic graph for Problem 3