Find the lateral area, help

1. what is the formula for finding the vertical distance between two points on a coordinate plane?

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?

Asequence is defined recursively using the formula f(n + 1) =f(n) - 5. which sequence could be