A samplemean, samplesize, population standarddeviation, and confidence level are provided. Use this information to complete parts(a) through(c) below.

x=53, n=15, =7, confidence level=99%

a. Use theone-mean z-interval procedure to find a confidence interval for the mean of the population from which the sample was drawn.

The confidence interval is from _______ to_______.

(Type integers or decimals rounded to one decimal place asneeded.)

b. Obtain the margin of error by taking half the length of the confidence interval.

What is the length of the confidenceinterval?

________

(integer or decimal rounded to one decimal place asneeded.)

c. Obtain the margin of error by using the formula E=z2

n.

Identify the critical value.

z2=

(integer or decimal rounded to two decimal places asneeded.)

What is the margin of error obtained using the methods of parts(b) and(c)?

________

(integer or decimal rounded to one decimal place asneeded.)