Shruti's daughter arshika need to be picked from the school every day. shruti asks one of her colleagues to pick her from school. shruti devised a password mechanism to confirm that arshika goes with the correct person only. the password on monday was sam16. the password on wednesday was hrw39. what will the password for friday?

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?