Graph a third degree polynomial with 3 zeros

Which of the fallowing best completes the sequence 12,8,5, a) 1 b) 2 c)4 d)0

Do 12/14 and 8/10 have the same value? explain your answer.

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?