The standard deviation of the pollution by-products released in the burning of 1 gallon of gas is 2.3 ounces. A random sample of 20 automobiles tested produced a standard deviation of 1.9 ounces. Is the standard deviation really less than previously thought? Use α = 0.05.

Which situation could best be represented by this linear equation? 24x + 38y = 520 > if x represents the number of bracelets and y represents the number of rings, there were 24 more bracelets sold than rings. the total sales were $520. if x represents the number of bracelets and y represents the number of rings, there were 38 more bracelets sold than rings. the total sales were $520. if x represents the number of bracelets sold at $24 each and y represents the number of rings sold at $38 each, the total sales were $520 if x represents the number of bracelets and y represents the number of rings, there were 520 bracelets and rings sold. bracelets were $24, and rings were $38. e