The earth's free-fall acceleration varies from 9.780m/s2 at the equator to 9.832m/s2 at the poles. A pendulum whose length is precisely 1.000 m can be used to measure g. Such a device is called a gravimeter: a. How long do a 100 oscillations take at the equator? b. How long do 100 oscillations take at the north pole? c. Suppose you take your gravimeter to the top of a high mountain peak near the equator. There you find that 100 oscillations take 201 s. What is g on the mountain top?