Can you help me solve this question, please?

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?

At the "no mutants allowed" country farm, every sheep has 4 legs, every chicken has two legs, and all animals have only 1 head. asked to count how many sheep and chicken are in the fields, a farm boy reports back that there are 140 feet and 50 heads. how many sheep and chicken are there? there are sheep and chicken at the farm.

Three consecutive even numbers have a sum between 84 and 96. a. write an inequality to find the three numbers. let n represent the smallest even number. b. solve the inequality. a. 84 ≤ n + (n + 2) + (n + 4) ≤ 96 b. 78 ≤ n ≤ 90 a. 84 < n + (n + 2) + (n + 4) < 96 b. 26 < n < 30 a. 84 < n + (n + 1) + (n + 2) < 96 b. 27 < n < 31 a. n + (n + 2) + (n + 4) < –84 or n + (n + 2) + (n + 4) > 96 b. n < –30 or n > 31