第一项不恰当。与计价和分摊目标相关的审计程序是针对单笔应收账款实施的，应将明细表中列示的每一笔应收账款定义为抽样单元。

第二项恰当。

(误受风险影响审计效果，误拒风险影响审计效率，因此误受风险的后果更为严重，故可接受的误受风险水平应低于误拒风险水平。)

第三项不恰当。仅实施函证程序无法证实应收账款的计价和分摊认定。A注册会计师应同时实施分析应收账款账龄、检查坏账准备计提等必要审计程序。

第四项不恰当。使用统计抽样时，如果预计只发现少量差异，不应使用比率法和差额法。

第五项不恰当。在计算抽样风险允许限度时，需要利用可接受的误受风险系数，与可接受的误拒风险系数不相关。

[Answer]

(1)inappropriate. The audit procedures related to the target of valuation and allocation is performed for every single account receivable transaction; it is required to define every, single account receivable transaction as sampling unit on  the transaction lists.

(2)appropriate. The acceptance risk has adverse impact on the effectiveness of audit; rejection risk has adverse impact on the efficiency of audit. Therefore, the outcome of acceptance risk is more serious, thus the acceptable level of rejection risk should be lower than that of the level of acceptance risk.

(3)inappropriate. The valuation and allocation of account receivable cannot be confirmed if only carrying out confirmation procedures. A CPA should carry out the analysis of accounts receivable check bad debt provisions, and other necessary audit procedures at the same time.

(4)inappropriate. If only  small  differences  are found in audit sampling, then the ratio estimation sampling and difference estimation sampling should not he used.

(5)inappropriate. The coefficient of acceptable acceptance risk should be used in the calculation of the limits of sampling risk, which is not related to the coefficient of acceptable rejection risk.