The height of the eiffel tower is 1050 feet. from the top, the angle of depression to a soccer ball on the ground is 20 degrees. find, to the nearest foot, the distance from the soccer ball to the base of the eiffel tower.

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?