Answer:
d. 4.
Explanation:
Hello,
In this case, the required number on milligrams is:
[tex]0.007502x10^{-26}g*\frac{1000mg}{1g}=7.502x10^{-26}mg[/tex]
It means that it has four significant figures which are counted for 7, 5, 0 and 2, considering that zero as it is to the right of first nonzero digit (7).
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