The number of significant figures in 5.400 are?

Answer 1

Trailing zeros after a decimal point are not normally written. As trailing zeros have been written they must be significant; thus 5.400 has 4 sig fig.

For example 5.400 could be 5.3996 rounded to 4 sig fig.

Answer 2

4 significant figures is correct answer of this question

Answer 3

Since the zeros after the 4 and not before, they are not significant.