A、B类泡沫灭火装置的特点：（）。
A.后座力小
B.携带方便
C.喷射范围大
D.操作简单
参考答案：A, B, C, D
人体能够完成特定的动作是因为（ ）
A．神经系统的调节
B．神经系统的收缩
C．肌肉的自然收缩
D．骨骼的自由运动
When the dispute over duty payment arises between the duty payer and the Customs, the duty payer should first pay the duty and then, within ______ of the issuance of the duty memo, apply to the Customs in writing for a reconsideration of the case.
A．10 days
B．20 days
C．30 days
D．one year
