Pollution and altitude: In a random sample of 300 cars driven at low altitudes, 48 of them exceeded a standard of 10 grams of particulate pollution per gallon of fuel consumed. In an independent random sample of 145 cars driven at high altitudes, 20 of them exceeded the standard. Can you conclude that the proportion of high-altitude vehicles exceeding the standard is less than the proportion of low-altitude vehicles exceeding the standard? Let P1 denote the proportion of low-altitude vehicles exceeding the standard and P2 denote the proportion of high-altitude vehicles exceeding the standard. Use the a= 0.05 level of significance and the P-value method with the TI-84 Plus calculator.