a random sample of 40 college students has mean annual earnings of 3245 and a standard deviation of 567 assuming that the population has a normal distribution estimate the mean annual earnings of college students including a margin of error how would the answer change of you increased your sample size to 360 students

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?