左心室射血分数(LVEF)正常值是()
A.≥60%
B.≥50%
C.≥40%
D.≥30%
E.≥70%
参考答案:B
— Could you tell me _?
—Sorry, I don’t know.
A. When will the plane take off B. When the plane will take off
C. When would the plane take off
马克思主义政治经济学的基础理论是
A.剩余价值理论 B.资本流通理论C.劳动价值理论 D.经济危机理论