Please ans the question:

QUESTION 1 (10 MARKS) (a) In a study of women's IOU-meter performance of 25 university students, mean time is 19.5 seconds with standard deviation of 9.88 seconds were recorded. Construct a 90% condence interval to estimate the mean. (b) In a random sample of 360 food stores, it was found that 160 of these food stores offers special promotions. Construct a 99% condence interval to estimate the population of food stores that offers promotion. QUESTION 2 (IS MARKS) (a) The company ABC introduce a new drug test method, 350 subjects were tested and results from 33 subjects were incorrect (either false positive or false negative). The company claims that the incorrect test reSults will be less than 10%. Test this claim using a:=0.05. (b) A random sample of 16 steel beams has a mean compressive strength of 58400 psi (pound per square inch) and population standard deviation of 652 psi. Using 99% signicance level, test if the true average compressive strength of steel is 58000 psi