Question

How many significant figures are there in the following number ?
$8000$

Answer 1

$\text{Four}$.

However, if expressed in scientific notation as $8\times {10}^3,$ it will have only one significant figure, as $8.0\times {10}^3,8.00\times {10}^3$ or $8.000\times {10}^3,$ it will have 2, 3 or 4 significant figures.