A father and his two sons wanted to measure the distance between the two tallest trees in the City Garden by their footsteps. It was winter and there was a fresh snow in the garden, so they decided to start measuring from the same tree by walking one after another straight to the other tree. The father's footstep is 32 inches long, while the same for his sons is 28 inches and 24 inches. In what distance, in feet, the three footsteps would overlap first time?

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?