Cuál es el primer paso para realizar un adecuado marco teórico

Describe alvord's tone in the two paragraphs on the history of dartmouth and its native american studies program (paras. 21-22)?

Long-term alcohol use can cause major depression. a. true b. false

Which of these is a disadvantage of hydrogen fuel cells? a. engines that use hydrogen fuel are more efficient than gasoline-powered engines. b. the only emission produced by hydrogen fuel cells is water. c. hydrogen fuel is continually available and useful for heating. d. hydrogen fuel is often purified in a process that emits lots of greenhouse gases.