Four significant figures.
One significant figure.
All of them are significant.
4 significant figures.
4 significant figures.
Four significant figures.
3
231.57 has five significant figures/numbers. All the numbers in 231.57 are significant.
.020 has two significant figures: 2 and 0 A significant figure are digits that contain meaning contributing to precision. All numbers are considered meaningful except for zero, unless zero is between two other numbers or tailing non zero numbers where a decimal is present.
5 significant figures.
2 significant figures.
One significant figure.
All of them are significant.
4 significant figures.
4 significant figures.
The figure 18.03 has a total of four significant numbers
Three. All nonzero numbers are significant, and any zeros in between significant numbers are significant.