Find the mean of the data set:
2.5,9,13,6,4 5, 8, 12, 12,6

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?

Flvs question 3 exam: 04.10 segment one exam part two what is the measure of angle x? picture is shown

Ratio of circumference to diameter example plz i need to now what it looks like.