19 Select the ranges D7:F12 and A15:G21 and format the cells so that when the sheet is 3 protected, the selected ranges are not locked. Protect the sheet and be sure the top check box to protect the worksheet and the first two check boxes in the list are selected. Enter the password go. 20 On the Winter Program Revenue sheet, in cell B4, create a DAVERAGE function to calculate 5 the average of the Amount field for the Lessons category. The Criteria range has been set up for you in the range A3:A4. In cell C4, create a DSUM to calculate the total of the Amount field for the Lessons category. Format the range B4:C4 using Accounting Number Format