Answer to Question 1
Climate issues associated with global warming from carbon dioxide emissions could limit the amount of coal burned in the United States, especially with the help of campaigns like Beyond Coal.
Answer to Question 2
Since some problems cross state lines (such as acid rain, water pollution, and ozone depletion), the federal government needs to have a role in environmental policy. Unfortunately, history shows that the administration and political party in power at a particular time has an enormous effect on the way policies are enforced. Through subsidies and tariffs, the federal government can encourage practices that are not environmentally sound. Ideally, the federal government should have the ability to enact and enforce laws but have a limited ability to change or undermine these laws depending on who or what party is in office, or which corporation or interests have the strongest influence. State governments should have the ability to have stronger policies than the federal government. For example, some states have stricter rules on the uses of wetlands or have bottle laws; however, states should not have the ability to usurp or undermine federal policy.
Possible relationships between fossil and living primates.
Comparing fossil patterns of the Hadar Baby, the Taung Child, and Au. Robustus.
Surface Coal Mine Reclamation
Selective Resources for Pharmacology
U.S. Subsurface Coal Mining: Output, Price, and Output per Worker-Hour, 1949–1994
The origin and spread of modern H. sapiens, reconstructed from genetic and fossil evidence.