Sample Of Greeting During A Church Program 6.27- ... A Random Sample Of 20 Greeting Cars Indicates An Average Value F $1.67 And A Standard Deviation ...?

6.27- ... A random sample of 20 greeting cars indicates an average value f $1.67 and a standard deviation ...? - sample of greeting during a church program

A stationery to greeting cards you have, the average sales value in your inventory. A sample of vehicles allowed 20 shows an average value of R $ 1.67 and a standard deviation of 0.32 U.S. dollars.

a) Assuming a normal distribution, the creation of a 95% confidence interval, the average value of all the greeting cards in the store inventory.
b) How the results of a) might be useful to help shop owners to appreciate the full value of your inventory?

Thank you!