Medical billing errors and fraud are on the rise. According to onestudy, 4 out of 5 times, the medical bills received by patients are not right. Complete parts(a) through(d) below.

a. If a sample of 9 medical bills isselected, what is the probability that exactly 0 bills will containerrors?

The probability is

nothing

.

(Type an integer or decimal rounded to four decimal places asneeded.)

b. If a sample of 9 medical bills isselected, what is the probability that exactly 6 bills will containerrors?

The probability is

nothing

.

(Type an integer or decimal rounded to four decimal places asneeded.)

c. If a sample of 9 medical bills isselected, what is the probability that more than 7 bills will containerrors?

The probability is

nothing

.

(Type an integer or decimal rounded to four decimal places asneeded.)

d. What are the mean and standard deviation of the probabilitydistribution?

The mean is

nothing

and the standard deviation is

nothing

.