Question 1 Each person in a random sample of 225 male teenagers and a random sample of 306 female teenagers was asked how many hours he or she spent online in a typical week. The sample mean and standard deviation were 15.1 hours and 11.3 hours for males and 14.1 and 11.8 for females. (Use a statistical computer package to calculate P.)

Question 2 To determine if chocolate milk was as effective as other carbohydrate replacement drinks, nine male cyclists performed an intense workout followed by a drink and a rest period. At the end of the rest period, each cyclist performed an endurance trial where he exercised until exhausted and time to exhaustion was measured. Each cyclist completed the entire regimen on two different days. On one day the drink provided was chocolate milk and on the other day the drink provided was a carbohydrate replacement drink. Data consistent with summary quantities appear in the table below. (Use a statistical computer package to calculate the P-value. Use ?_{chocolate milk} ? ?_{carbohydrate replacement}. Round your test statistic to two decimal places, your df down to the nearest whole number, and the P-value to three decimal places.)

t=

df=

p=