1
Five significant figures.
1 of them.
Three
5 of them.
5 of them.
4 significant figures.
Five significant figures.
1 of them.
Four, assuming that 7.000 is written in that form to indicate that it has 4 significant figures.
2
two
Three
5 of them.
Six of them.
5 of them.
5 of them.
3 of them.