How many countries are in the world​

Which two essential elements of geography are missing from the image above? a. “location” and “region” b. “movement” and “places” c. “humans and the environment” and “movement” d. “places and regions” and “human systems”

How long does it take neptune to orbit the sun?

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?