1.【答案】C。
解析：Material stores control account账户左边为流进账户的项目，右边为从账户流出的项目。(1)应该改为direct materials returned from production were $13,000。
知识点：Accounting for material costs (Chapter 6 Accounting for material)
2.【答案】A。
解析：Annual holding cost = (EOQ/2 + buffer inventory)×Ch
= (9,000/2 + 600) × 1.5
= $7,650
知识点：EOQ (with bulk discount) (Chapter 6 Accounting for material)
