汽轮机冷态启动和增加负荷过程中，转子膨胀大于汽缸膨胀，相对膨胀差出现（）增加。
A、正胀差；
B、负胀差；
C、不变；
D、无法确定。
参考答案：A
What worried the child most was _____________ to visit his mother in the hospital.[ ]
A. to his being allowed
B. his not being allowed
C. not his being allowed
D. not his allowed
第一题：许可证办理（15分）张三在A市B县（已设立烟草专卖局）开了一家“明明食杂店”，想从事烟草专卖品零售业务，于2012年10月21日向有权机关提出办理申请，有权机关经审查认为张三的申请符合法定条件，依法做出准予许可决定，并向张三送达了零售许可证正副本。请根据材料回答下列问题:
根据相关规定，烟草专卖零售许可证的持证人在许可证有效期内哪些登记事项发生变化的，应当依法申请变更？（3分）
