Which set of lengths are the side lengths of a right triangle? (9,15,17) (14,23,25) (20,30,40) (15,36,39)

Jayne is studying urban planning and finds that her town is decreasing in population by 3% each year the population of her town is changing by a constant rate

What situation is an example of an observational study

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?