5. Refer to the preceding exercise. The youths also responded to a battery of questions that provides a measure of perceived parental support. This measure had sample means of 46 (s=9) for the single-mother households and 42 (s = 10) for the households with both bio-logical parents. Consider the conclusion, "The mean parental support was 4 units higher for the single-mother households. If the true means were equal, a difference of this size could be expected only 2% of the time For samples of this size. 95% of the time one would expect this difference to be within 3 4 of the true value " Explain how this conclu- sion refers to the results of

a) a confidence interval.

b) a test.