Division number story with an answer of 12/8?

What is the slope of the line that contains the points (4,8) and (9,8)? what type of line is it?

Let w=23 . what is the value of w + 45 ?

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?