What is the area of trapezoid DEFG with coordinates D (2, 3), E (5, 3), F (3, 1), and G (2, 1)?

2 square units
3 square units
4 square units
8 square units

Which three lengths could be the lengths of the sides of a triangle? 21 cm, 7 cm, 7 cm 9 cm, 15 cm, 22 cm 13 cm, 5 cm, 18 cm 8 cm, 23 cm, 11 cm

15 and 14.7 are 1 apart, so 15 – 14.7 must be 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?