Answer:
an object that is at rest will stay at rest inless a force acts upon it.
An oject that is in motion will not change its velocity unless a force acts upon it.
<span><span>Atomic number36,</span><span>Atomic mass<span>83.80 g.mol -1,</span></span><span>Density<span>3.73 10-3 g.cm-3 at 20°C,</span></span><span>Melting point- 157 °C,</span><span>Boiling point<span>- 153° C</span></span></span>
Your answer would have to be #3
Air pollution exist in two forms namely ozone and particle pollution. CFCs and smog are under the ozone form of pollution. Ozone type of pollution is mostly formed by reaction between the sunlight and the vapors that are emitted due to human activities.