4. A company wants to compare four programs for training workers to perform a certain manual task. Twenty new employees are randomly assigned to the training programs, with 5 in each program. At the end of the training period, a test is conducted to see how quickly trainees can perform the task. The number of times the task is performed per minute is recorded for each trainee, with the following results: \begin{tabular}{CCCC) Program 1 & Program 2 & Program 3 & Program 4 W \hline & & & 9 & 10 & 12 & 9W 12 & 6 & 14 & 8 W 14 & 9 & 11 & 11 W 11 & 9 & 13 & 7 13 & 10 & 11 & 8 \end{tabular) Estimate the treatment effects for the four programs. S.P.PB. 264