Answer :
Answer:
Slow
Explanation:
The longer you make the pendulum, the slower the grandfather clock. The shorter you make the pendulum, the faster the grandfather clock
The grandfather clock when calibrated correctly at sea level runs faster.
What is Calibration?
This involves the use of traceable reference device to determine the measuring deviations in the complete measuring instrument.
The time at sea level is slower while that on the mountain is faster which is why the clock will run faster as the calibration was done on the sea level. This therefore makes option B the most appropriate choice.
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