Help
End Section Review
End Exam
Answer Edit Confirmation
课程
活动
资料
反馈
题目内容
Several studies (i) the assumption that paper cups, because they were made of natural products, were more environmentally (ii) than cups made of plastic (polystyrene). Indeed, these studies indicated that the environmental (iii) of producing and recycling paper cups were similar to, if not more than, those related to the production, disposal, and recycling of polystyrene cups.
学员15inyq
学员11xbxa
学员17pivy
学员15kzve
学员11ckgw