题目

Many new means__________ to prevent the river ____________. A. have found, from polluting B. have found, from being polluted C. have been found, from being polluted D. has been found, from being polluted 答案：C全世界每年有成百上千人由于误吃毒蘑菇而死亡，鹅膏草碱就是一种蘑菇的毒素，它是一种呈环状的八肽。若20种氨基酸的平均相对分子质量为128，则鹅膏草碱的相对分子质量大约是A．1024B．898 C．880D．862