Bartow Photographic Services takes wedding and graduation photographs, At December 31, the end of Bartow's accounting period, the following information is available:

a. All wedding photographs are paid for in advance, and all cash collected for them is credited to unearned revenue. Except for a year-end adjusting entry, no other entries are made for revenue from wedding photographs. During the year, Bartow received $42,600 for wedding photographs. At year-end, $33,900 of the $42,600 had been earned. The beginning-of-the-year balance of unearned revenue was zero.

b. During December, Bartow photographed 60 members of the next year's graduating class of Shaw High School. The school has asked Bartow to print one copy of a photograph of each student for the school files; Bartow delivers these photographs on December 28 and will bill the school $5.00 per student in January of next year.

Revenue from photographs ordered by students will be recorded as the orders are received during the early months of next year.

c. Developing and printing equipment rent of $18,000 for one year beginning on August 1 was paid on August 1 to Nikon. When made, the payment was debited to prepaid rent.

d. Depreciation on the firm's building for the current year is $14,400.

e. Wages of $4,170 are owed but unpaid and unrecorded at January 31.

f. Supplies inventory at the beginning of the year was $3,200. During the year, supplies costing $19,600 were purchased from Kodak. When the purchases were made, their cost was debited to supplies inventory. At year-end a physical inventory indicated that supplies costing $4,100 were on hand.

Required:

1. Prepare the adjusting entries for each of these items.

2. By how much would net income be overstated or understated if the accountant failed to make the adjusting entries?