Suppose you slice through a square pyramid such that the plane is parallel to the base and halfway up the total height of the pyramid. How does the Side length of the cross-section compared to the side length of the base?

Rockwell hardness of pins of a certain type is known to have a mean value of 50 and a standard deviation of 1.1. (round your answers to four decimal places.) (a) if the distribution is normal, what is the probability that the sample mean hardness for a random sample of 8 pins is at least 51?