3. Consider results of 20 randomly chosen people who have run a marathon. Their times, in minutes, are as follows: 137, 146, 150, 163, 166, 179, 186, 193, 196, 213, 218, 225, 236, 239, 254, 269, 271, 279, 282, 295. Calculate a 90% upper confidence bound on the mean time of the race. Assume distribution to be normal. Hint: the population variance is known or unknown

Frank has $66.50 in his account on sunday. over the next week, he makes the following changes to his balance via deposits and purchases: day debit ($) credit ($) monday 60.33 80.75 tuesday 54.45 wednesday 49.20 15.00 thursday 35.40 friday 16.85 75.00 saturday 80.56 on what day does frank first get charged an overdraft fee? a. wednesday b. thursday c. friday d. saturday select the best answer from the choices provided a b c d

Simplify. (-2)^-3 a. -8 b. -1/8 c. 1/8 d. 8

Lines a and b are parallel. what is the value of x? -5 -10 -35 -55