Final answer:
To determine if cars are better at meeting pollution standards than they used to be, a hypothesis test at a 99% confidence level can be performed by comparing the average car pollution from the current period to historical data using a t-test or a z-test.
Step-by-step explanation:
To perform a hypothesis test at a 99% confidence level to determine if cars are better at meeting pollution standards than they used to be, we can set up the following hypotheses:
Null hypothesis (H₀): The average car pollution is the same as it used to be.
Alternative hypothesis (H₁): The average car pollution is better than it used to be.
Next, we need to collect data on car pollution from the Department of Transportation in South Africa. We will compare the average car pollution from the current period to historical data and conduct a t-test or a z-test to determine if there is a significant difference.
If the test statistic falls in the rejection region of the appropriate statistical test, we can reject the null hypothesis and conclude that cars are indeed better at meeting pollution standards than they used to be with 99% confidence.