蓄电池储存地有何要求？
参考答案：
要求通风设施良好、干燥（最好装空调），保持环境温度在25℃左右；地面承受能力要强。
He found it hard for Alan to focus on his teachers for longer than five minutes, _________ if the lecture was boring.
A．extremely
B．especially
C．basically
D．naturally
车载台的发射功率一般为（）w。
A.20.0
B.40.0
C.60.0
D.80.0
