The probability that student fred sotiropulus takes history 101 next semester is 0.6 and the probability that he takes psychology 101 is also 0.6. what is the probability that he takes at least one of these two courses next semester?

A20? -foot ladder is placed against a vertical wall of a? building, with the bottom of the ladder standing on level ground 19 feet from the base of the building. how high up the wall does the ladder? reach?

Find the slope of a line given the following two points

Mrs. morton has a special reward system for her class. when all her students behave well, she rewards them by putting 3 marbles into a marble jar. when the jar has 100 or more marbles, the students have a party. right now, the the jar has 24 marbles. how could mrs. morton reward the class in order for the students to have a party?