Response to the following questions:
1. Describe what is meant by a sampling unit. Explain why the sampling unit for verifying the occurrence of recorded sales differs from the sampling unit for testing for the possibility of omitted sales.
2. Distinguish between the TER and the CUER. How is each determined?
3. What is meant by an attribute in sampling for tests of controls and substantive tests of transactions? What is the source of the attributes that the auditor selects?