Use PROC LIFETEST to: Create a plot showing the product-limit estimates of the survival curves for patients with and without low MMSE at baseline. Complete the following table of estimated survival probabilities: Probability of surviving for: MMSE <= 25 at baseline MMSE > 25 at baseline 2 years 3 years 5 years Perform the log-rank and Wilcoxon tests of the null hypothesis that patients with and without low MMSE have the same survival distribution. State your conclusions. Use a graphical method to evaluate the assumption of proportional hazards between those with and without low MMSE at baseline