There are 2 significant figures in this measurement.
There are 3 significant figures
It has 2 significant figures. However, the fact that it is given as 2300 mm and not as 230 cm suggests that it is, in fact significant to 4 figures.
Two significant figures, 6 and 7.
3 0s to the left are insignificant and 0s that aren't right after the decimal or between other significant figures are insignificant
5 significant figures.
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.
Four.
There are four significant figures in 0.00301 cm. The non-zero digits (3 and 1) and zeros between them are all considered significant.
It has 2 significant figures. However, the fact that it is given as 2300 mm and not as 230 cm suggests that it is, in fact significant to 4 figures.
All three of them are significant figures