Kn 4f =9v solve for n

Plz me plz i will give a brain just plz

Which of the following is true about the graph of f(x)=7^x. select all that apply. a= it intercepts the x axis b=it intercepts both axis c=it intercepts neither d=it intercepts the y axis

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?