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Select the correct answer.
Consider event A and event B. What is the probability that event Boccurs, given that event A has already occurred?

The graph shows the distance y, in inches, a pendulum moves to the right (positive displacement) and to the left (negative displacement), for a given number of seconds x. how many seconds are required for the pendulum to move from its resting position and return? enter your answer in the box.

The fence around a quadrilateral-shaped pasture is 3a^2+15a+9 long. three sides of the fence have the following lengths: 5a, 10a-2, a^2-7. what is the length of the fourth side of the fence?

How many sides does a regular polygon have if each exterior angle measure is 45 degrees explain your answer, i really don't understand this.