The average salary for a welder is $36,600 per year. a lawyer makes on average $113,530. if you consider the earning potential of both over a 30 year period, what is the difference between the welder's earnings as compared to the lawyer's wages? $76,930$984,470$2,307,900$3,369,300

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?