会计师事务所应当自审计报告日起，对审计工作底稿至少保存（）年。
A.5
B.7
C.10
D.12
参考答案：C
His English is improving _______, which makes both his parents and his teacher happy.
A．now and then
B．little by little
C．sooner or later
D．one after another
FMIS系统应加强资金流向控制，防范报账资金支付风险，制定现金结算最高额度，原则上单笔（）元以上的大额开支应使用支票、汇款等转账支付结算方式。
A.1000元
B.2000元
C.3000元
D.4000元
