An audit associate is preparing an audit program for the audit of a client's allowance for doubtful accounts. To gather evidence in support of the valuation assertion, the associate included the following audit procedure in the audit program:

Confirm accounts receivable by sending positive confirmations to a sample of customer account balances.

1. a.Evaluate the relevance of the procedure in addressing the valuation assertion.
2. b.Comment on the reliability of the evidence gathered using the procedure.