Guangzhou （Xinhua news agency）——12 people were killed and 20 injured early yesterday morning when they jumped from a burning train car into the path of an oncoming (即将到来的) goods train in Southern China. When No.247 Wuchang —— Guangzhou passenger train was passing the Dayaoshan Tunnel in Guangdong Province, South China at 00 :17 hours yesterday, a fire caused by passengers' smoking broke out on No.17 car. They wanted to extinguish fire. However, while the train was stopping, some frightened passengers jumped from windows. As a result, 12 passengers were crushed to death and 20 others were injured by an opposite northward passing goods train-No.1766.
小题1:What was the cause of the fire？
A．A heavy rain.
B．High temperature.
C．Carelessness.
D．Fear.小题2:When did the accident happen？
A．At 00:17 am.
B．At 00:17 pm.
C．At seventeen past one
D．At seventeen to one小题3:Where did the accident happen？
A．In Wuchang.
B．In Guangzhou.
C．In Hubei.
D．In Guangdong.小题4:The underlined word “extinguish” in the passage most probably means .
A．put out
B．put up
C．come up
D．come out小题5:In which direction did the passenger train travel？
A．Northward.
B．Southward.
C．Eastward.
D．Westward.
的圆环，圆环与竖直放置的轻质弹簧上端相连，弹簧的下端固定在水平地面上的A点，开始弹簧恰好处于原长
．现让圆环由静止沿杆滑下，滑到杆的底端（未触及地面）时速度恰好为零，已知当地的重力加速度大小为
．则在圆环下滑的整个过程中
