a) American households spent an average of about $70 in 2007 on Halloween merchandise such as costumes, decorations and candy. To see if this number had changed, researchers conducted a new survey in 2008 before industry numbers were reported. The survey included 2100 households and found that average Halloween spending was $47 per household. The sample mean is dollars, while the claimed population mean is dollars. b) The average GPA of students in 2001 at a private university was 3.38. To assess whether this has changed over time, a survey on a sample of 190 students from this university was taken in the Spring 2020 semester. The survey yielded an average GPA of 3.75. The sample mean is and the claimed population mean is