Eight classes from Hillsboro Middle School collected a total of 4,496 books for the library book sale. If each class collected the same number of books, how many did each class collect? A.560 books
B.562 books
C.570 books
D.572 books

The random variable x is the number of occurrences of an event over an interval of ten minutes. it can be assumed that the probability of an occurrence is the same in any two-time periods of an equal length. it is known that the mean number of occurrences in ten minutes is 5.3. the appropriate probability distribution for the random variable

Find the center and the radius of the circle with the equation: x^2-2x+y^2+4y+1=0?

Aword processing program requires a 7- digit registration code made up of the digits 1,2,4,5,6,7 and 9 each number has to be used and no number can be used mor than once how many codes are possible