i have a few questions i cant figure out.....

1. When converting from cash basis to accrual basis accounting, which of the following adjustments should be made to cash receipts from customers to determine accrual basis service revenue?
a subtract ending accounts receivable
b subtract beg unearned service revenue
c add ending accounts receivable
d add cash sales

2. when converting from cash basis to accrual basis accounting, which of the following adjustments should be made to cash paid for operating expenses to determine accrual basis operating expenses?
a + beg accrued liab
b + beg prepaid expenses
c - ending prepaid expense
d - interest expense

3. which of the following is a real account?
a goodwill
b sales
c accounts rec
d both goodwill and accounts rec

4. which of the following is a nominal account?
a unearned rev
b salary expense
c inventory
d retained earnings

5 If inventroy account at the end of the year is understated, the effect will be to
a overstate the gross profit on sales
b understate the net purchases
c overstae the cost of goods sold
d oversate the goods available for sale

What will the implications be if the Cost of Sales figure is understated ?