What is the number of significant digits in the measurement 104.100 m?

6

6 significant digits

Explanation:

Number of significant digits of a number are the number of digits that carry a relevant contribution to the measurement.

For the case above;

104.100

rule - all digits to the right of the decimal of any number equal or greater than 1 will count as a significant digit.

104.100 - --.100 (the three digits counts)

And since the the digits to the left are none zero digits, so they all count as significant digits.

104.100 - - - 104 (the three digits counts)

The total number of significant digits,

Since all the digits of the number 104.100 will count as a significant digit.

The number of significant digits is equal to the number of digits in the number.

N = 6

6 significant digits