What mnemonic device can help you remember all the countries of the Middle East

Why is terracing used in southeast asian agriculture?

Which of these fragmental sedimentary rocks would most likely form farthest from the land?

The first atomic explosion was detonated in the desert north of alamogordo, new mexico, on july 16, 1945. what percentage of the strontium-90 ( yr) originally produced by that explosion still remains as of july 16, 2016?