Around 1950, petroleum surpassed coal as the leading energy resource used in the united states. which statement best explains this change?
after 1950, americans started using an increasing amount of renewable energy resources to generate electricity.

after 1950, americans stopped using electricity that was generated by coal-fired power plants.

as more americans started driving automobiles, the consumption of energy derived from petroleum drastically increased.

prior to the late 19th century, wood was the leading energy resource consumed in the united states.

Which of the following initial observations would more directly lead to this research study? a) ginko biloba is cost effective and also possesses heart-protective, antioxidant, anti-inflammatory properties. b) metformin is an effective treatment of patients with t2d, but shows side effects that complicate the disease state. c) over the past several years, the cost of treating t2d within the united states has increased dramatically. d) many plants contain molecules that improve the health and quality of life of patients with a variety of diseases like t2d. e) t2d affects millions of individuals in the usa and worldwide many of who could benefit from improved therapies.