4. Suppose that the initial height of the object were measured from the top of the object at the release point to the floor. How would this affect your experimental result for g, that is,
would it be too high or too low? Is this a random or a systematic error? (See Experiment 2
on errors.)

If a rock is thrown upward on the planet mars with a velocity of 12 m/s, its height (in meters) after t seconds is given by h = 12t − 1.86t2. (a) find the velocity of the rock after two seconds. m/s (b) find the velocity of the rock when t = a. 12−3.72a m/s (c) when will the rock hit the surface? (round your answer to one decimal place.) t = s (d) with what velocity will the rock hit the surface? m/s