发生或者可能发生传染病暴发、流行时,省、自治区、直辖市人民政府应当在接到报告()内,向国务院卫生行政主管部门报告
A、30分钟
B、1小时
C、2小时
D、12小时
参考答案:B
His sister wanted to have him ____ the radio, but he had had it ____ already.[ ]
A. repair, repair
B. to repair, repair
C. repaired, to repair
D. repair, repaired
简述文丘里-皮托管测量原理。