3

Depends how much cereal you have.

Usually a 3 quarter cup.

Though you may have created this question to recieve an indefinate answer, cereal comes in boxes (and other containers) of all different shapes and sizes. There are tiny cereal cups that are about 3 inches high and about 4 inches in diameter, tiny cereal boxes that are on average 3 to 4 inches high and 2 to 3 inches wide, and a variety of larger cereal boxes. If you are asking for an average for regular cereal boxes, I would say between 8 and 12 inches tall, and 7 and 10 inches wide.

3-dimensional rectangle.

135units3

depends on the type of cereal