1.A pharmaceutical company is testing a new cold medicine to determine if the drug has side effects.To test the drug, 7 patients are given the drug and 8 patients are given a placebo (sugar pill).The change in pulse rate (beats per minute) after taking the pill was as follows:

Given drug:

3

7

2

8

2

5

6

Given placebo:

2

4

1

1

2

0

2

3

Test to determine if the drug raises patients' pulse rate more than the placebo using = 0.025

2.Corn plants grow to a mean height of 6.43 feet with a standard deviation of 0.15 feet and the distribution of heights is approximately normal.A new genetically modified corn plant is being developed.A researcher grew a group of 27 genetically modified corn plants and found that their mean height was 6.51 feet.Test to determine if the genetically modified plants are taller using =0.01.

3.A recent poll of 2,800 US adults found that 1862 of them had voted in the recent election.Make a 95% confidence interval for the percent of all US adults who voted.(Hope you were one of them, if you are eligible!!)

4.From the population of all Americans with high cholesterol, which has a mean cholesterol level of 265 mg/dL with a standard deviation of 37, Isis Pharmaceuticals chose 39 patients for treatment with its new antisense drug.After treatment, the patients in the study had a mean cholesterol level of 252.Test to determine if the antisense drug lowered the cholesterol using = 0.01 and the prob-value approach.

5.The IRS claims that it takes 87 minutes to prepare a tax form.You believe it takes longer than 87 minutes.You ask 21 tax filers and find the following preparation times:

64, 69, 75, 75, 87, 89, 94, 96, 97, 98, 98, 99, 100, 100, 105, 108, 110, 112, 119, 122, 128

Determine if the preparation time is significantly longer than 87 minutes.Use= .05.