The triangle shown is rotated 90° counterclockwise about the origin. What are the new coordinates of point A? A)
(1,2)
B)
(-2, 1)
C)
(2, 1)
D)
(-2,-1)

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?