5 significant figures.
2 of them.
12.655 cm rounded to four significant figures is 12.66cm
All three of them are significant figures
102.3 cm
The number 210 has two significant figures. In scientific notation, it would be written as 2.1 x 10^2 to explicitly show the two significant figures. Significant figures are the digits in a number that carry meaning contributing to its precision and accuracy. In this case, the digits 2 and 1 are considered significant in the number 210.
5 significant figures.
There are 4 significant figures in this number.
There are 2 significant figures in this measurement.
4.05 has three (3) significant figures
There are 3 significant figures
None. The abbreviation cm represents one or more centimeters. In your question there are no numbers associated with the cm unit, therefore there are no significant figures.
2 of them.
12.655 cm rounded to four significant figures is 12.66cm
There are two significant figures in the measurement 210 cm.
There are four significant figures in 0.00301 cm. The non-zero digits (3 and 1) and zeros between them are all considered significant.
3 of them.