Thank you for reporting, we will resolve it shortly
Q.
Which of the following has the least number of significant figures?
Physical World, Units and Measurements
Solution:
According to the rules of significant figures.
$1.64 \times 10^{20} kg$ has three significant figures.
$0.006 m ^{2}$ has one significant figures.
$7.2180 J$ has five significant figures.
$5.045 J$ has four significant figures