Statistical literacy for a binomial experiment with rr successes out of nn trials, what value do we use as a point estimate for the probability of success pp on a single trial? select one: a. p hat = n-r b. p hat = n+r c. p hat = n/r d. p hat = r/n

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?