某300MW并网运行的机组的δ=6%，在电网频率从49.8Hz升到50Hz时，机组的功率变化为（）。

材料请回答 16～22 Smoking Since 1939, numerous studies have been conducted to determine whether smoking is a health hazard.The trend of the evidence has been consistent and indicates that there is a serious health risk.Research teams have conducted studies that show beyond all reasona-ble doubt that tobacco smoking is associated with a shortened life expectancy （）And low tar tobacco are claimed to make smoking to some extent sa-fer, but they can only slightly reduce,not eliminate,the hazards． 第 16 题 It is easy to determine whether smoking is hazardous． A．RightB．WrongC．Not mentioned

A、*
B、CustomerCode, Name, Hometown, Sex, Email, Telephone, LoginTime, PassWord
C、CustomerCode, Hometown, Telephone, Name, Sex, Email, LoginTime, PassWord
D、CustomerCode ~ PassWord

A.28000
B.27000
C.27500
D.25000