Thirty gpas from a randomly selected sample of statistics students at a college are linked below. assume that the population distribution is approximately normal. the technician in charge of records claimed that the population mean gpa for the whole college is 2.84. a. what is the sample mean? is it higher or lower than the population mean of 2.84? b. the chair of the mathematics department claims that statistics students typically have higher gpas than the typical college student. use the four-step procedure and the data provided to test this claim. use a significance level of 0.05.