Below are some diagnostic plots for a fitted simple linear regression model. Please select all correct statements regarding the model assumptions and unusual observations. Residuals vs Fitted Normal O-Q Sip Resdish 70 100 Filed values Thereelical Quanille Leverage Cook's distance 0.05 0 04 Cook's distance Leverage 0.00 0.05 0.10 0.15 0.20 0,25 0.02 0.00 13 18 23 28 33 38 43 48 53 58 Obs. number Select one or more: O a. There are no obvious high-leverage points. O b. Compared with other points, observation 53 is an influential observation and it could be a possible outlier. O c. Independence assumption is violated. O d. Linearity assumption is violated. O e. The residuals are slightly light tailed. O f. Constant variance assumption can be accepted since no severe non-constant variance problem appears