A sample of size

=

n

66

is drawn from a normal population whose standard deviation is=

8.8

. The sample mean is=

x

49.82

.

Part 1 of 2

(a) Construct a

99.8

%

confidence interval for

. Round the answer to at least two decimal places.A99.8

%

confidence interval for the mean is

<

<

.

Part 2 of 2

(b) If the population were not approximately normal, would the confidence interval constructed in part (a) be valid

?

Explain.The confidence interval constructed in part (a)

(Choose one)

be valid since the sample size

(Choose one)

large.