What detemines the precision of a calculated result based on measurement?

Answer 1

The precision of any measurement comes from the equipment being used, instruments that can measure in smaller increments are more precise, as they can measure closer to the true value. For example if you used a ruler to measure the thickness of a wire, you may get a result of 2mm, but if you measure the same wire with a micrometer you may get a result of 1.8mm - the micrometer can measure in smaller increments, so the result is more precise.