1.60 A statistics lecturer studied the average time (in hours) her students spent studying per week and the marks (in %) they scored in the final examination of the first semester. The following are the partial results collected by her at the end of the semester.

18, 712 16, 442 110, 862 15, 202 111, 892 The first number is time (in hours), and the second is marks. Plot the data.