00.4463 has four significant figures
Significant figures are digits in a measurement that contribute to its precision.
They include all certain digits and the first uncertain digit. Leading zeros, trailing zeros after a decimal point, and placeholder zeros are counted as significant figures.
The number 00.4463 has four significant figures.
Leading zeros (zeros to the left of the first non-zero digit) are not considered significant, but zeros between significant figures and trailing zeros after a decimal point are counted.