Number of microns present in 4km is 4 * 10^9 μm
We know that
1km = 10^3m
So,
4km = 4 × 10^3m
and
1μm = [tex]10^{-6} \\[/tex] m
No. of microns in 4 km = 4 km / 1 μm
= 4 * 10^3 / 10^-6
= 4 * 10^9 μm
The micrometre, also referred to as a micron, is a measure of length in the International System of Units that is equal to one millionth of a meter, or 1106 meter. The nanometre, which is one billionth of a meter or one thousandth of a micrometer, is the smallest common SI unit.
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