At garden mart ,bella bought g packets of geranium seeds in packets of marigold seeds and z packets of zinnia seeds. all of the plant seeds were on sale for half price. the expression shown below repression shown below represent the total cost of the plant seeds bella bought.1.48g

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?