A computer magazine wants to rate four software programs used to prepare annual federal income tax forms based on the amount of time needed to complete the form. The study will select individuals who have incomes less than $100,000 and who itemize their deductions. Determine how many individuals would be needed for each software program to declare a difference in the average completion times at the a = .05 level of significance with a power of .90 if the difference between any pair of means is greater than 30 minutes. From previous studies using similar software, the standard deviation in completion time is thought to be about 12.25 minutes.