What is the area formula for a trapezoid prism

Which of the following is the shape of a cross section of the figure shown below

Find the roots of the polynomial function f(x) = x^3 + 2x^2 + x

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?