The boy didn't know what the population of China _________.[ ]
A. are
B. was
C. were
答案:B
女性,42岁,左侧胸痛5个月,胸闷、气短,渐加重,渐消瘦。X线胸片示左侧胸腔积液,CT示左侧胸膜凹凸不平,则最可能的诊断是()
A.肺结核球
B.阿米巴肺脓肿
C.肺癌
D.细菌性肺脓肿
E.支气管扩张并肺部感染
商品消费部门的垄断程度越高,商品需求的波动幅度 ( )
A.越大 B.越小C.不变 D.无法确定