Final answer:
The total of all the credit entries for the payroll for the week ending May 28 is $2,800.
Step-by-step explanation:
The total of all the credit entries for the payroll for the week ending May 28 can be calculated by subtracting the total deductions from the gross earnings.
Total credit entries = Gross earnings - Total deductions
Total credit entries = $4,000 - $1,200 = $2,800
Therefore, the total of all the credit entries for the payroll for the week ending May 28 is $2,800.