At the beginning of the summer, the water level of a pond is 2 feet below its normal level. After an unusually dry summer, the water level of the pond dropped another 1 1/3 feet. Write an equation to show how far above or below the normal water level the pond is at the end of the summer.
Plz help, math is not my best subject and I'm confused!

Which of the binomials below is a factor of this trinominal? x^2-13+30

True or false: the graph of y=f(bx) is a horizontal compression of the graph y=f(x) if b< 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?