For the final project of an analytical chemistry laboratory course, the students were asked to quantify the lead (Pb2+) content in a drinking water sample. To receive a passing grade for the project, the students must produce a result (Pb2+ concentration) that agrees with the result obtained by the course professor, who was using the same method, at the 95% confidence level. The mean ( x), standard deviation (sx) and number of replicate measurements (n) are shown for the data obtained by the professor (p) and one student (s) chosen at random. Student: x's = 5.150 ppb Ss = 0.199 ppb ng = 6 Professor: = 5.800 ppb Sp = 0.110 ppb np = 6 Calculate the F value. Fcalc = Are the standard deviations from the professor's and student's data sets significantly different from each other at the 95% confidence level? The value of Ftable can be found in the table of critical F values. yes no Calculate the value of tcale to compare the data sets from the student and the professor at the 95% confidence level. I calc = Did the student receive a passing grade for the final project? A list of t values can be found in the Student's t table. no yes