2 of them.
2
0.3 has one significant figure.
Three.
2000 has one significant figure. A significant figure is any non-zero digit or any embedded or trailing zero. Leading zeros are not significant.
1 significant figure.
There are 5 significant figures, the six plus the four zeroes. The zeroes are significant figures due to the inclusion of the decimal - with no decimal there would only be one significant figure (the six).
It has 1 significant figure.
0.004 has 1 significant figure.
1 significant figure. It can also be written as 4x10^6 (one sig fig)
Two significant figure
1 significant figure.
It has 1 significant figure.
3 significant figures.
3 significant figures.
One significant figure
1 significant figure.
10 significant figures.
One significant figure.