根据以下材料，回答21-35题 Los Angeles has planted 2,000 rubber trees d
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根据以下材料，回答21-35题
Los Angeles has planted 2,000 rubber trees down the middle of one of its main streets. These trees do not 21 rubber. They are,22,made of rubber. Mr. Joe Dynamo, a spokesman for Los Angeles 23 council, explained the reasons. He said:"These 24 are representative of our virtual society. We have polystyrene grass on our golf 25. We have non-milk powder 26 our coffee. We 27 copies in plastic of old wooden furniture.We have fiberglass tombstones.28__________ shouldn´t we have trees made of rubber? "
At 50 miles an hour,29 motorist will see any difference. And our preservation 30 will be lower. You give the trees an annual rinse(清洗 with detergent, and 31 them off twice a year. We 32 a lot of money because transplanting, pruning, weeding and leaf-collection are all 33. And we have a 60-year 34 guarantee on each plant. This is rationalization at 35best."
第31题答案是（ ）
