You are a researcher studying a certain species of fish in a local lake.  You gather a random sample of 17 fish of this species and record the lengths (in centimeters) of the fish. The data is displayed in the table below.  Estimate the mean length of all fish of this type in the lake.  Use a 80% confidence level.

8	6.4	8.2	6.9	10.4	7.1	9.8	7.9	8.4	6.3
9.5	4.7	8.2	8.6	7.7	8.4	9.1

(Checksum: 135.6)

a)  State the parameter of interest, and verify that the necessary conditions are present in order to carry out the inference procedure.

b) Find the critical value and standard error.

Critical Value:     Standard Error:

c)  Find the confidence interval:  (,) 

d) Interpret your 80% confidence interval in context.

e) Interpret the confidence level (not this specific interval).  What does it even mean to be 80% confident?