Biogas is a renewable, as well as a clean, source of energy. Biogas plants significantly curb the greenhouse effect: the plants lower methane emissions by capturing this harmful gas and using it as fuel. Biogas generation helps cut reliance on the use of fossil fuels, such as oil and coal.
The American Indian groups or Native Americans had no idea of money and no economies, not until the European immigrants introduced it to them. Even though a lot of time has passed when they were introduced to the ideas of economy and money, a lot of them declined the use of money as they believed that money is evil in nature.
20: checks and balances!
21: Duties: execute law, enforce law, make laws. who does them? EXECUTIVE branch EXECUTEs laws, LEGISLATIVE branch makes laws, and JUDICIAL branch ENFORCES the laws. making sure they are constitutional.
