With valid citations and reference lists in APA format, respond to the colleagues' posts below and provide a constructive comment on their assessment of diagnostics. 1. Were all assumptions tested for? 2. Are there some violations that the model might be robust against? Why or why not? 3. Explain and provide any valid additional resources (i.e., web links, articles, etc.) to provide your colleague with addressing diagnostic issues. "The study aimed to determine the impact of respondents' age, race, and highest degree on their income. A multiple regression model was conducted using the General Social Survey, with the dependent variable being respondents' age and the independent variables being their highest degree and race. The results showed no correlation between the residuals, and the model was found to be accurate. However, the scatterplot showed variability in the model's predictions, suggesting potential heteroscedasticity. The lack of a clear pattern in the residuals across predicted values suggests that the assumptions of linearity and homoscedasticity need further investigation. The study suggests that a different model or transformation might be more appropriate for the data