Please help me 7th grade math

What are the first 4 terms in the multiplication pattern given by the formula 2×4n

Hey am have account in but wished to create an account here you guys will me with my make new friends of uk !

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?