I think I’ll go with C. long dry cold winters
D. Low side pressure is high and high side pressure is low
Two atoms of oxygen element are represented as "20". The two oxygen atoms are unreactive state and are unstable readily reacts and form molecules.
O₂ reprersents one molecule oxygen. When the two oxygen atoms reacts with each other forms one molecule of Oxygen. After the formation of Oxygen molecule, it (oxygen) has got stability.
