成本动因的分类有()
A.环境动因
B.技术动因
C.资源动因
D.作业动因
参考答案:C, D
化疗对下述哪种肿瘤疗效最好()。
A.卵巢上皮癌
B.子宫内膜癌
C.绒毛膜癌
D.子宫颈癌
E.内胚窦癌
Read, look and answer. (根据图片所示回答问题)
1. What are they?
___________________________
2. How many hens are there?
3. Are they horses?