帷幕灌浆段长度特殊情况下可适当缩减或加长，但不得大于（）m。
A.5
B.10
C.15
D.20
参考答案：B
With the address to help him he had no ____ in finding her new house.
A．difficulties
B．difficulty
C．troubles
D．mistkes
受全球金融危机的影响，2008年某家电商城的销售额由第二季度的800万元下降到第四季度的648万元，则该商城第三、四季度的销售额平均下降的百分率为[ ]
A．10%
B．20%
C．19%
D．25%
