I have no yuuuuu to say anything abt to
Answer:
4
Explanation:
The zeros before a non zero digit do not count as significant figures so there are 4 sig figs in the number
When it is acted upon by an outside force
The chemical makeup found on the periodic table.
B, radon is correct. Interestingly, it often collects in basements from radioactive decay of rocks such as granite that contain uranium. Because it is an unreactive noble gas and because it is denser than air it sits in basements and must be pumped out. It collects in human lungs and is the second leading cause of lung cancer behind smoking.