C. The Treaty of Versallies. This treaty was the most important of the peace treaties that brought an end to World War One. It punished Germany harshly for it's part in the war.
Pretty sure it is C because it it divisible by 3. If you divide 15 you get 5 and if you divide 6 you get 2.
Southeast. Johnny Cash is from Arkansas, Dale Earnhardt is from South Carolina and Elvis is from Mississippi.
Gravity exerts a downwards force on the roots.