Consider the Population Regression Model: log(earnings) = Bo + Bieduc + B2AfrAmerican + u, where log(earnings) = weekly log-earnings in U.S. dollars, educ=educational attainment in years, AfrAmerican=1 if the worker is African American, and 0 otherwise. 1a. How do you interpret the slope on educ, Bi? Show formally in terms of the conditional mean and explain in words. 1b. Assuming that the returns to education are positive, and African Americans earn less than non-African Americans, graph the sample regression function. Be sure to label all axes, intercepts and slopes, as well as the equation for each PRF