Help pls There are 50 balls in a box, numbered 1, 2, 3,… 50. One ball is taken out of the box at random. What is the probability that the number of the ball taken out contains the number 2?

Solve the equation 3x2 + 19x + 9 = 0 to the nearest tenth.

Evaluate the expression for the given value of the variable 7a - 4a for a =8

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?