Can y’all me with 7 - 12 showing work. will be giving brainliest: )) and for 13 and 14 i need too : )) :

Combine the information in the problem and the chart using the average balance method to solve the problem.

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?

If f(x) = 4x - 3 and g(x) = x + 4, find (f - g) (x)