The easiest way of knwing the answer is trough the etymology of the words. Orographic comes from the ancient greek word <em>oros.</em>
Orographic lifting occurs when an air flow or air mass finds itself obligated to go over a mountain range since it cannot go trough the sides (mountain ranges are to long for that).
Answer: These 2 are called the double helix made up of sugar and phosphate groups. Attached to each sugar is one of four bases--adenine, cytosine, guanine, and thymine.