Question

Which measurement has three significant figures?
Responses

7.8×10−6g
7.8 times 10 to the power of negative 6 lowercase g

100 g

100 g

0.089 g

0.089 g

1.02×10−3g

Answer 1

1.02×10−3 g

Reason: In scientific notation all digits shown are significant, so 1.02 has three significant figures. (For comparison: 7.8×10−6 has 2 sf; 0.089 has 2 sf; 100 g as written is ambiguous but normally 1 sf.)