Question

how many zeros appearing in the number 0.0040500 are significant

Answer 1

in this number 5 digits are significant and 3 zeros are significant

Answer 2

Hey mate !!

Here's the answer !!

The number of zeros that are significant are the zeros added before the digit 5.
Any number with zeros after the decimal without any natural number is considered insignificant.

Example:

1.01000 Here the number of zeros is 4 but the number of significant zeros is only 1.

Hence the number of significant zeros in the number 0.0040500 is 3 zeros that are present before the number 405.

Hope my answer helps !!

Cheers !!