7. At the bottom of the hill, the toboggan moving 12 m's forward accelerates at -0.50 m/s- for 10 s. What is the toboggan's velocity at the end of the 10 s? Show the equation used and all steps. 8. How much time does it take a car travelling south at 12 m/s to increase its velocity to 26 m/s south if it accelerates at 3.5 m/s south? Show the equation used and all steps. 9. The acceleration of a freely falling object (near Earth), when we assume no air resistance, is (remember units). 10. The assumption of no air resistance is never totally true, but is often close enough to make pretty accurate calculations. Discuss cases where this is a really good assumption and when it isn't. 11. A stone is dropped from a cliff. What is it's velocity after 1 second? After 2 seconds? 12. A ball is thrown straight up into the air at 14 m/s. How long does it take for the ball to slow down to an upward velocity of 6.0 m's? Show the equation used and all steps. 13. If you throw a rock up into the air, when is its velocity zero? What is the acceleration when the velocity is zero? 14. A rock is thrown downwards with an initial velocity of 8.0 m/s. What is the velocity of the rock after 1.5 s