1. What are the new issues and challenges facing the U. S. in the 21st Century?

This refers to weather and atmospheric conditions measured over a long period of time.

In a small, closed economy, national income (gdp) is $350 million for the current year. individuals have spent $100 million on the consumption of goods and services. they have paid a total of $60 million in taxes and the government has spent $75 million on goods and services this year. use this information and the national income identity to answer the questions. how much does the economy spend on investment?

Martha participates in a research study in order to receive extra credit for her psychology class. when she arrives in the research office she is given a can of what looks and tastes like beer, but which actually contains no alcohol. in the adjoining room martha's classmate karen is also participating in the study. karen receives a can of alcoholic beer. if the experiment was designed to test the effects of alcohol on concentration, then who is exposed to the independent variable?