Question

how many significant figures do they have? 1.068,54,0.008,1002*43.2

Answer 1

1.068 has 4, the zero is between 2 other significant figures so it is significant
54 has 2
0.008 has 1 because you can rewrite it as 8*10^-3
1002*43.2, the product will have 3 significant figures

Answer 2

actually if 54 is exactly 54, then it has infinite significant figures