计算某年某地平均每千人口中活产数的指标是 A．粗出生率 B．总生育率 C．

“Just sign here, sir,” the postman said as he handed Oscar a package.

The package consisted of a long, narrow      carefully wrapped in brown paper. Opening the box, Oscar saw an umbrella inside—a very old one with a beautiful handle (把手).      he had not seen it in more than 20 years, he recognized it immediately.

Oscar was 16 when he first saw the unusual umbrella. He had gone to a      with his grandparents. As they were leaving, he noticed an umbrella on an empty seat. Shocked by its beauty, Oscar wanted to find its    . He asked the manager of the theatre to look up the record of ticket sales. The name was Mrs. Brain. It was hard work to find     Mrs Brain lived. However, they managed to get there.

Oscar rang the bell of Mrs. Brain’s house. The door opened, and an elderly woman appeared. “May I help you?” she asked.

“I’d like to return it if it’s yours,” Oscar said, holding out the umbrella.

“Why, yes! It’s mine,” replied Mrs. Brain with a     smile and shining eyes. “It was given to me by my father years ago. Thank you so much for returning it. ”

“May I offer you a reward for your     ?”

“No, madam,” he said, “My grandmother says a good deed is its own reward.”

“Well, that’s      my father used to say. What is your name, young man?”

Years later, Oscar was       the handle of the umbrella as he remembered Mrs. Brain. It was in perfect condition, considering how old it was. Why had it arrived here today?

As if in answer, a note fell from the paper. It read, “I want you to      this umbrella as a present for a kind, unselfish action long ago.” Oscar was deeply moved with tears.

不支持病毒性心肌炎诊断的是（）

A.感冒后即出现胸痛

B.血清心肌酶增高

C.病毒中和抗体滴度增高

D.体温升高与心率增快不相平行

E.严重者可出现高度房室传导阻滞及心源性休克

心动周期中冠状动脉血流量急剧减少是在

A．心室等容收缩期
B．心室等容舒张期
C．心室舒张期的后期
D．心室舒张期的早期

计算题：某班的K₁为1.0，K₃为0.98，求该班的K₂是多少？

试验发动机时，不得在车下工作。