Justine went swimming six days this week at her local pool. use the following lengths of time spent at the pool to determine the mean absolute deviation. 40 minutes, 50 minutes, 90 minutes, 60 minutes, 80 minutes, 70 minutes a. 65 b.15 c.50 d.55

Each person in an it department of 25 people works on at least one of 3 major projects: system security, program implementation, platform development. 10 people work on system security, 13 work on program implementation, and 12 work on platform development. 4 people work on system security and platform development, 5 people work on program implementation and platform development, and 2 people work on all three projects. how many people work on system security and program implementation?