【简答题】你的国家有什么食物是别的地方吃不到的?请介绍一个用它做的菜。(最少200个字,请用课文里学过的词和语法,用得越多越好。 )
【单选题】If the marginal cost of producing the next unit of output exceeds the average total cost, then:
A.
the average total cost curve is increasing.
B.
the marginal cost curve is at its minimum.
C.
the average total cost curve is decreasing.
D.
the average total cost curve is at its minimum.
【单选题】Average total cost (ATC) is calculated as follows:
A.
a. ATC = (change in total cost)/(change in quantity of output).
B.
b. ATC = (change in total cost)/(change in quantity of input).
C.
c. ATC = total cost/quantity of output.
D.
d. ATC = total cost/quantity of input.
【判断题】环节动物的血液呈红色,是因为血细胞中含有血红蛋白。
【单选题】If an increase in output results in a decrease in average total cost, the corresponding marginal cost is:
A.
. less than average total cost.
B.
. greater than average total cost.
C.
. equal to average total cost.
【简答题】“螳螂捕蝉,黄雀在后”,形容人们做事时常常顾此失彼。我国内蒙古自治区东乌旗牧区,“草肥水美”。牧民们世代在这里居住和放牧。在1960年以前的草原上还生存有狐狸、狼、野驴等动物。牧民为了不让狐狸、狼等把小羊羔吃掉,连续几年捕杀狐狸、狼。1980年以后,狐狸和狼在这一地区最终消失了。人们发现成群的野驴也看不到了。但人们更加吃惊的发展原来美丽的草原也渐渐失去了绿色,有的地方暴露出了一块一块黄沙地。198...