Supposexhas a distribution with a mean of80and a standard deviation of9. Random samples of sizen=36are drawn.

(a)Describe thedistribution.

has a normal distribution.

has a Poisson distribution.

has a binomial distribution.

has a geometric distribution.

has an approximately normal distribution.

has an unknown distribution.

Compute the mean and standard deviation of the distribution. (For each answer, enter a number.)

=

mu sub x bar =

=

sigma sub x bar =

(b)Find thezvalue corresponding to=83. (Enter an exact number.)

z=

(c)FindP(<83). (Enter a number. Round your answer to four decimal places.)

P(<83) =

P(x bar < 83)