2
2300.m has four significant figures.
Two of them
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 (2,3).
Five significant figures.
4 significant figures.
The value 24.503 has 5 significant figures.
2 significant figures.
5 of them.
Three
two
1