Use the formula to determine the number of black squares in the first five figures of the Sierpinski Carpet given by the partial sum: For this sum:
a1 = 1
r = 8
n = 5

The number of squares in the first five figures is = 4681

A. 127 cm^2 b. 144.5 cm^2 c. 172 cm^2 d. 50 cm^2

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?

How can i differentiate this equation?