The director for Weight Watchers International wants to determine if the changes in their program results in better weight loss. She selected 25 Weight Watcher members at random and compared their weight 6 months later to weight at the start of the program.The results are in this excel file:

Weight Watchers.xlsx

(The weight in the column labeled "After" represents their weights six months later and "Before" represents their weight at the start of the six-month period.) The director used .05 as the significance level.

Use Excel to test. For each paired difference, compute After - Before. In Data Analysis, t-Test: Paired Two Sample for means, select the After data for Variable 1 Range. Note that the critical value output by Data Analysis for this test is always positive. In this problem, the sign of the critical value is negative corresponding to a 1-tailed test with lower reject region and negative lower critical value.

What are the Null and Alternate Hypotheses?

(Keep the Excel file open for the next parts of the question.)

H0: After - Before 0; HA: After - Before < 0

H0: After - Before = 0; HA: After - Before 0

H0: After - Before 0; HA: After - Before > 0

H0: After - Before > 0; HA: After - Before 0