1. Suppose we want to determine whether height above sea level has an impact on the boiling temperature of a certain liquid. Two independent samples are taken. The first sample of size 80 taken at the coast shows a mean boiling temperature of 78 degrees Celsius and a standard deviation of 5 degrees Celsius. The second sample of size 100 taken inland has a mean boiling temperature of 80 degrees Celsius and a standard deviation of 10 degrees Celsius. Construct a 95% condence interval for the mean difference between the two populations. 2. Two procedures were developed in research laboratory to purify oil, namely procedure A, which is quite simple and quick, and procedure B, which is considerably more expensive. Preliminary tests yielded the following results: 71A = 13 f... = 817.4538 5.1 = 16.8041 113 = 15 3 = 829.706? 33 = 10.5?33 Construct a 90% condence interval for the difference between the two population means. 3. A medical doctor claims that the proportion of female patients with high blood- pressure is different from the proportion of male patients with high blood- pressure. The doctor conducted a survey in his practice. Out of the 100| female patients only 13 had high blood-pressure and out of the 110| male patients, 33 had high blood-pressure. Construct a 99% condence interval for the difference between the two population proportions, interpret the interval