The Salem Board of Education wants to evaluate the efficiency of the town’s four elementary schools. The three outputs of the schools are

■ Output 1 = average reading score

■ Output 2 = average mathematics score

■ Output 3 = average self-esteem score

The three inputs to the schools are

■ Input 1 = average educational level of mothers (defined by highest grade completed: 12 5high school graduate; 16 5college graduate, and so on)

■ Input 2 = number of parent visits to school (per child)

■ Input 3 = teacher-to-student ratio

The relevant information for the four schools is given in the file P04_42.xlsx. Determine which (if any) schools are inefficient.