Johanna graphed the number of calls she made during one day. How many calls were made before 6 Cell Phone Calls 12 10 Numberof calls 6 2 10 a. m.- 11:59 a. m. 12 p. m.- 1:59 pm 2 p. m.- 4 p. m.- 3:59 pm 5:59 p. m. Time of Day 6 p. m.- 7:59 p. m. 8 p. m.- 9:59 p. m.​

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?