6. Listed below are speeds (miles/hour) measured from southbound traffic on 1-280 near

Cupertino, CA. This simple random sample was obtained at 3:30PM on a weekday.

62 461-61+ 57+ 61+54 +59 +58 +59 +69+60 +67,

a. Construct a 99% confidence interval estimate of the mean of speeds for southbound traffic

near Cupertino, CA.