QUESTION 6 A study is concerned with measuring the technical efficiency of a group of colleges affiliated to a university, using the DEA method. It was limited to three inputs (number of students, number of employees and number of teachers) and three outputs (number of conferences and seminars, number of published scientific research and number of graduates). The following table summarizes the inputs and outputs of each decision unit (university) during the academic year 2020-2021. number of graduates 121 61 200 72 89 Outputs number of number of published scientific research 29 16 26 18 10 conferences and seminars 9 3 10 5 2 number of teachers 51 62 54 71 82 Inputs number of employees 70 80 65 75 90 number of students 1623 1912 1875 2100 2988 DMU's Number (college) 1 2 3 4 5 To improve the relative efficiency of College No. 4, it is necessary to increase the number of teachers approximately by O2 teachers Ob.5 teachers 4 teachers Od 9 teachers