There are three.
In 30900 there are [at least] three significant figures.
30.900 has 5 significant figures.
3 in A+
4 significant digits.
There are three.
In 30900 there are [at least] three significant figures.
30.900 has 5 significant figures.
3 in A+
Three. The two zeros on the end are just placeholders. 30900 has 3 significant figures.
4
It has two significant digits.
3 significant digits.
It has 3 significant digits.
4 significant digits.
Five. All nonzero digits are significant and zeros in between significant digits are significant.
Five. All nonzero digits are significant and zeros in between significant digits are always significant.