急性心肌梗死时,缓解疼痛最有效的药物为().
A.吗啡
B.硝酸甘油
C.硝苯地平
D.地西泮
E.消心痛
参考答案:A
A.条件(1)充分,但条件(2)不充分.
B.条件(2)充分,但条件(1)不充分.
C.条件(1)和(2)单独都不充分,但条件(1)和条件(2)联合起来充分.
D.条件(1)充分,条件(2)也充分.
E.条件(1)和(2)单独都不充分,条件(1)和条件(2)联合起来也不充分.
22x-1+2x>1. (1)-1<x<0; (2)x≥0.
For us Senior Three students, believing that our hard work will______can build up our confidence. [ ]
A. take off
B. pay off
C. keep off
D. get off