6. A researcher wants to test if the average grade of student in a particular major is over 80. The null hypothesis to conduct a statistical test on this theory would be The population mean is greater than 80 The population mean is less than or equal to 80 The population mean is less than 80 The population mean is greater than or equal to 80 7. A researcher claims that more than 30% of a certain population is single. The p-value associated with the appropriate statistical test is 0.25. Which of the following statements is correct: There is no evidence to conclude that more than 30% of the population is single Conclude that more than 25% of the population is single Conclude that more than 30% of the population is single Conclude that exactly 25% of the population is single