For Exercises assume that the variables are normally or approximately normally distributed. Use the traditional method of hypothesis testing unless otherwise specified.

Healthier diets generally involve lower sodium amounts. The American Heart Association recommends less than 2300 mg of sodium daily. (One teaspoon of table salt contains 2400 mg of sodium!) A random sample of prepared foods has the sodium amounts listed below. Is there sufficient evidence to conclude at α = 0.05 that the standard deviation in sodium amounts in prepared foods exceeds 150 mg?

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