Please explain no copy paste

Seven groups of students in a lab section measured the same unknown sample to determine sulfur by gravimetric method, reported as, 803%. The results are as follows. After Q-tests, all the numbers are retained. If the section average is 11.17%, the standard deviation is 0.77 and the true value is 12.00%, which of the following statement is correct at 90% confidence level? (a). No systematic error since Ttable Tcalc (c). Systematic error present since Ttable Tcalc (e). Not enough information given