Which of the following situations involves testing a claim about a single population proportion? Group of answer choices A certain prescription allergy medicine is supposed to contain an average of 245 parts per million (ppm) of a certain chemical. The manufacturer takes a sample to check whether the mean concentration is the required 245 ppm or not. A recent study estimated that 20% of all college students in the United States smoke. The head of Health Services at Goodheart University suspects that the proportion of smokers may be lower there. According to the College Board, which administers the SAT exam, the average score for females is lower than for males among graduating seniors in 2011. An educational researcher wants to test whether this is also true in her school district. A Statistics student at Tacoma Community Colleges wants to determine whether there is a difference in the proportions of class meetings that male and female students attend.