为便于维护人员操作，机柜和设备前预留的空间至少应为______mm。
A．1000 B．1500 C．1800 D．2000
参考答案：B
Are there any similarities and differences between the Oral Approach and the Audiolingual Method in terms of language theories and learning theories
肝素引起的自发性出血，其解救药物是
A．止血环酸B．维生素KC．维生素CD．鱼精蛋白E．氨甲苯酸
