There's one, because after the decimal point the first non zero number is 6.
6 significant figures.
5 significant figures.
Two - all nonzero digits are significant.
2 significant figures
There are 6 significant figures in this number.
6 significant figures.
6 significant figures.
6 significant figures.
6 significant figures.
6 significant figures.
6 significant figures.
6 significant figures.
6 significant figures.
6 significant figures.
6 significant figures.
6 significant figures.
6 significant figures.