Pretty sure it's the Precambrian.
Yes explosion is mainly energy
Answer:
The United States took first steps to keep the air clean.
Explanation:
The US environmental protection agency was created in the year 1970 so this option is wrong.
November 15, 1990 however was a milestone in keeping the air clean, the signing f the amendments, the amendments set the stage for protecting the ozone layer, improving air quality and visibility.
The correct option is option A; The United States took first steps to keep the air clean.
Answer:
Neutron
Explanation:
Neutrons has a neutral or no charge.
