If a1 = 3 and an = nan-1 + 2 then find the value of a4.

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Pls urgent max amount of points will be given and pls do not answer if unsure or you will be reported by me and brainliest answer gets the brainliest .. thing so yeh

Which fraction is equal to 1hole and 2/5? a.3/5 b.75 c.57 d.73

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?