1. Explain the meaning of significant digits (or significant figures) in measurement. Significant Digits are used to indicate the uncertainty of a measurement
2. Why is the metric system used instead of the US customary system, and vice versa, in various parts of the world?
The metric system is used instead of the US customary system because mostly everywhere in the world uses it and vice versa for not using it. The US customary system is used in the United Stated of America and in some small 3rd world countries