Assume a researcher wants to examine the relationship between mean family income (the response variable) and age and years of formal education. However, the researcher believes that there is an interaction effect between age and education. The research estimates the following model: E(income) = B0 + B1*age + B2*education + B3*age*education All beta parameters were significantly different than zero, with the following estimates: B0 = 10, B1 = 30, B2 = 5, and B3 = 2. For an individual who is 30 years old, with 10 years of formal education, what would the predicted average income be? How do you interpret coefficient B3?