An online survey by the S porting Goods M anufacturers Association, a trade group o f sports retailers and marketers, claim ed th a t household incom e o f recreational athletes varies by sport (The Wall Street Journal, August 10, 2009). In order to verify this claim, an econom ist samples five sports enthusiasts participating in each o f six different recreational sports and obtains each enthusiast's incom e (in $1,000s), as show n in the table below:

Snorkeling Sailing Boardsailing/ On-road Off-road Windsurfing Bowling triathlon triathlon 90.9 87.6 75.9 79.3 64.5 47.7 86.0 95.0 75.6 75.8 67.2 59.6 93.6 94.6 83.1 79.6 62.8 68.0 98.8 87.2 74.4 78.5 59.2 60.9 98.4 82.5 80.5 73.2 66.5 50.9

a. Specify the com peting hypotheses in order to test the association's claim.

b. Create an ANOVA table.

c. At the 5% significance level, w hat is the critical value?

d. Do some average incomes differ depending on the recreational sport? Explain. P-69