9 + 7 + z + z + 5 + 7

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?

Which equation expression the relationship between the number of boxes b and the number of cans c and the proportion is 48

Amachine part consists of a half sphere and a cylinder, as shown in the figure. the total volume of the part is π cubic inches.