The present volume of water circulating through Earth’s surface system was attained approximately ___. A one million years ago B 50 million years ago during the age of the dinosaurs C 10,000 years ago soon after the end of the last glacial period. D four billion years ago soon after the Earth's crust formed

Use your vocabulary words to complete the sentences below. more of the world's population is now concentrated in heavily populated urban areas known as a this is quite a contrast from the past when or native groups were either farmers or — hunters and gatherers who moved between places in search of food. advanced technology has led to the integration of world economics and cultures, in the world's more developed countries. this integration requires , the responsible use and management of natural resources.

5. what is a red giant? can our sun become a red giant? why or why not?

In an effort to japan recover from the devastating effects of the 1929 depression, japanese military leaders in the 1930s formed an alliance with nazi germany negotiated more trade treaties with the soviet union closed its doors to western trade adopted a policy of imperialist expansion