A study to find a steel deposit under the ground is carried out by making gravity measurements, under the argument of th

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A study to find a steel deposit under the ground is carried out
by making gravity measurements, under the argument of the change of
acceleration of gravity due to the excess mass. A special
pendulum of a length that reaches an accuracy of 2.00000 meters is
used and the period of oscillation is measured at various points in
the area where the deposit is presumed to be. At a variation
of the order of one millionth of a second, how much will the period
change if the acceleration of gravity between two points changes
from 9.80000 m/s2 to 9.80010 m/s2? Use Pi=3.14159.