$A$ substance of mass $49.53 \ g$ occupies $1.5 \ cm^3$ of volume. The density of the substance (in $g \ cm^{-3}$) with the correct number of significant figures is:

What points should be considered during the multiplication and division of numbers with significant figures?

Assertion $(A)$: The number $0.00764$ has three significant figures.
Reason $(R)$: If the number is less than $1$,the zeros on the right of the decimal point but to the left of the first non-zero digit are not significant.

The area of a rectangular field (in $m^{2}$) of length $55.3 \ m$ and breadth $25 \ m$ after rounding off the value for correct significant digits is

The number of significant figures in $4.870 \ m$ is

The number of significant figures in all the given numbers $25.12, 2009, 4.156$ and $1.217 \times 10^{-4}$ is