极限的值等于:() ["t","-t","1","-1"]
毛细血管组成中,“小动脉和微动脉的管径小,对血流的阻力大”属于() ["交换血管","容量血管","后阻力血管","前阻力血管","毛细血管前括约肌"]
合介桶保留的悬浮液应使泵保持()米的压头。 ["1","1.2","1.3","1.5"]
下列不属于毒性药品的是() ["A.砒霜","B.砒石","C.生巴豆","D.制川乌","E.红粉"]
承诺必须具备的要件不包括()。 ["承诺只能由受要约人向要约人作出","承诺必须在有效期限内作出","承诺的内容必须与要约的内容完全一致","承诺必须是特定人的意思表示"]
世界上最大的岛屿在哪里?最大的群岛国家在哪里?