Three - all nonzero numbers are significant.
Three.
It has 1 significant figure.
0.004 has 1 significant figure.
There is one significant figure in 0.3.
There is one significant figure in .00000004.
1 significant figure. It can also be written as 4x10^6 (one sig fig)
1 significant figure.
1 significant figure.
1 significant figure.
1 significant figure.
1 significant figure.
1 significant figure.