1.We could know the number of significant figures by counting the non-zero numbers and the zeros in between the two non-zero numbers,we could also know the significant figures by identifying the zeros in the right that has a decimal on the left side.
2.Trailing zeros does not count as a significant figures and the zeros in the left side of a decimal.
Answers & Comments
ANSWER
1.We could know the number of significant figures by counting the non-zero numbers and the zeros in between the two non-zero numbers,we could also know the significant figures by identifying the zeros in the right that has a decimal on the left side.
2.Trailing zeros does not count as a significant figures and the zeros in the left side of a decimal.