A Chicago resident believes that "people are more stressed because of the current political climate" and would like to test their beliefs scientifically. Study Design 1: Two hundred people were questioned throughout the city as this person went about their day. Each perso in the sample was asked whether he or she "felt more stress over the past two months than the previous two months". The proportion of people who responded yes is .7. a) This study design is Observational Experimental Neither b) Did the study use random selection from some population? Yes No c) Did the study use random assignment to experimental groups? Yes No d) Is the conclusion "Chicago residents are more stressed because of the current political climate" appropriate given the study description? Yes No Explain your reasoning Search

Step 1 ：a) This study design is Observational. In this study, the researcher is observing and collecting data without manipulating any variables or conditions. The participants were not subjected to any treatment or intervention, but were simply asked about their feelings of stress. b) The study did not use random selection from some population. The participants were not selected randomly but were simply the people that the researcher encountered throughout their day. This could introduce selection bias, as the sample may not be representative of the entire population of Chicago. c) The study did not use random assignment to experimental groups. There were no experimental and control groups in this study, and thus no random assignment was possible. All participants were asked the same question without any variation in conditions or treatment. d) The conclusion "Chicago residents are more stressed because of the current political climate" is not appropriate given the study description. The study did not specifically ask about the political climate or establish a causal relationship between the political climate and stress levels. The increase in stress could be due to a variety of factors, not necessarily the political climate. Furthermore, the sample may not be representative of all Chicago residents, so the results cannot be generalized to the entire population. In order to establish a causal relationship between the political climate and stress levels, a more rigorous experimental design would be needed. This could involve randomly assigning participants to different conditions (e.g., exposure to news about the political climate vs. no exposure) and measuring their stress levels. Additionally, the use of validated stress measures would increase the reliability and validity of the results.