Find the inverse of f(x) = 1/2x + 3

Can someone me and plz do the problem

10 ! in a race, nick is 50 feet in front of jay after ten seconds. how fast can nick run, if jay can run 20 feet per second?

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?