A researcher hypothesized that adolescent girls are more invested in their romantic relationships than are adolescent boys. She asked adolescent partners to rate the total amount of time they engaged in activities centered around their relationship (e.g., seeing each other, thinking about the partner, talking about the relationship with others). In a sample of 41 couples, girls spent an average of 12 hours a week and boys an average of 10. The standard deviation of the difference was 1.5 hours. 

a) Calculate t. 

b) Was the research hypothesis supported? Explain.