What property can justify each statement (pic included) i will give 20 points please help asap!!!

Write a function that matches the description. a cosine function has a maximum of 5 and a minimum value of -5. f (r) =

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?

Which best explains why this triangle is or is not a right triangle ?