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1. Two friends enter the Boston marathon. The first friend runs at a constant speed of 0.500 m/s. The second friend holds a speed of 1.00 m/s. (a) How far ahead is the second friend after 2.00 hours? (b) If the second friend promises to stop after 2 hours and wait for his slower friend to catch up, how many hours would he be waiting once he stops? 2. Two forces of 6 N and 8 N act at right angles to one another on a 2-kg box. What is the resultant force in polar coordinates? Resultant acceleration? 3. If Suzie weighs 300 N on the Earth, how much will she weigh on the moon where the gravitational acceleration is 1/6 the acceleration on Earth? 4. A rock is thrown horizontally from a cliff that is above a lake's surfaces with a velocity of 12 m/s. (a) If it takes 6.00 seconds to splash into the lake, how high is the cliff? (b) How far from the cliff does the rock land? 5. A 28.0 kg student slides down a slide that makes a 25.0 angle with the horizontal. (What is the magnitude of the normal force that the slide exerts on the child? 6. A box of mass 2.3 kg slides along a horizontal floor. Its initial speed is 4.1 m/s but the force of friction causes it to stop after 3.1 s. What is the coefficient of kinetic friction between the box and the floor? 7. A massless spring stretches 10 cm when a load of 50 kg is suspended from it. How far will the spring stretch if a load of 70 kg is placed on the spring