The given quantity is 0.007 m2
If the number is less than one, then all zeros on the right of the decimal point (but left to the first non-zero) are insignificant. This means that here, two zeros after the decimal are not significant. Hence, only 7 is a significant figure in this quantity.b) 3
Here, the power of 10 is irrelevant for the determination of significant figures. Hence, all the digits are significant figures.
The quantity used as a standard of measurement is called unit.
Example: Unit of time is second.