List 7 integers that meat all the requirements two of the integers are 6 units apart but they are a little closer than two of the other integers of the integers that are 6 units apart, one of them is 2 units greater than the opposite of the other integer there are 5 negative numbers one integer is one unit greater than the opposite

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?