Discuss the specific actions that the EPA has taken to minimize ...

[KWilfred]

Discuss the specific actions that the EPA has taken to minimize the automobile emissions of lead, nitrogen oxide, and carbon monoxide.
 
  What will be an ideal response?

Question 2

How did Earth acquire its layered structure?
 
  What will be an ideal response?

[Tonyam972]

Answer to Question 1

In 1976 the EPA began regulating lead emitted from automobiles, particularly after it was found to deactivate the catalysts in automobile catalytic converters. All automobiles manufactured after 1975 had to have a catalytic converter installed in order to help reduce the emissions of carbon monoxide, hydrocarbons, and nitrogen oxides. Since 1980, the use of leaded gasoline has now been banned in most countries, and global emissions of lead have decreased by 90 since 1970.

Answer to Question 2

Chemical differentiation of the hot, molten, early Earth. The densest material sank to the interior (bottom) of Earth, and the lightest material floated to the top.