随着产量的增加,平均固定成本( )。
A.不断下降
B.先升后降
C.固定不变
D.不断上升
参考答案:A
This area of the park has been specially () for children, but accompanying adults are also welcome.
A.inaugurated
B.designated
C.entitled
D.delegated
出境观赏动物,应在动物出境前( )天持外贸合同或展出合约、产地检疫证书、国家濒危物种进出口管理办公室出具的许可证、信用证到出境口岸检验检疫机构报检。
A.15
B.45
C.30
D.60