3 options: A researcher wished to test the hypothesis that older men sleep less than younger men do. Random samples of 30-year-old men, 50-year-old men, and 70-year-old men were selected. Each subject was brought to a sleep laboratory and measured as to how many hours of sleep per night occurred. Is there a difference in sleep by age? ___________ is the dependent variable in this problem. ___________ is the independent variable in this problem. ___________ is the appropriate statistical test to use for this