Which federal agencies and cabinet departments are most important in determining the existence and causes of climate change?

Which federal agencies and cabinet departments are most important in determining the existence and causes of climate change? Secondly, which ones formulate and execute policies in response to assertions of climate change? Post by 9:55 pm (ET) on Friday MAY 16, 2014; include citations or URLs for your work to receive full credit; and, provide substantive replies to the posts of at least 2 of your classmates by 11:55 pm (ET) on Sunday. Assignment responses should be no less than 300 words and no more than about 500 words,