问题 单项选择题

计算机通过MIC(话筒接口)收到的信号是()。

A.音频数字信号

B.音频模拟信号

C.采样信号

D.量化信号

答案

参考答案:B

解析:

本题考查多媒体基础知识。

MIC(话筒)输出的是音频模拟信号,声卡从MIC获取音频模拟信号后,通过模数转换器(ADC),将声波振幅信号采样转换成一串数字信号并存储到计算机中。重放时,这些数字信号送到数模转换器(DAC),以同样的采样速度还原为模拟波形,放大后送到扬声器发声,这一技术称为脉冲编码调制技术(PCM)。

阅读理解

My husband Ollie had retired from teaching and we were making plans to travel together to Florida. Then he was terribly ill and became very weak, hardly able to speak. Weeks passed and it became clear that Ollie was near death, but I prayed day and night that he could get better.

One of us was always in Ollie’s hospital room—either me, or our grown children, Bruce and Karen. One day, in his broken and weak speech, Ollie told Bruce, “Go home. You should be with Gwen.” Gwen was Bruce’s wife. They had been married for six years and lived hundreds of miles away. Gwen was about to have a baby. We felt an extra sadness, knowing Ollie would never see his first grandchild.

“I don’t want to leave you, Dad,” Bruce said. Ollie repeated, “You should be with Gwen.” Reluctantly, Bruce left. “When the baby comes,” he promised Ollie, “you will be the first to know.” A few days later, around 2 p.m., Ollie awoke from a sleep. He turned and looked at me. I sat close to hear his weak words. “The baby is coming now. It’s a boy,” he said. For a moment his eyes were filled with tears. Then he went back to sleep again. Not long after that, Karen ran into the room. “Bruce called,” she said, a smile lighting her face. “Gwen gave birth to a healthy baby boy around two o’ clock.”

Ollie smiled; he had been the first to know. That night, Ollie died in his sleep.

小题1:Ollie didn’t travel to Florida because________.

A.he was too weak to travel

B.he could hardly be able to speak

C.he could not afford the trip

D.he was waiting for his grandchild to be born小题2:Why did Ollie want Bruce to be with Gwen?

A.Ollie thought it was too much trouble for Bruce to stay at hospital.

B.Ollie wanted Bruce to bring the baby along as soon as it was born.

C.Ollie didn’t want his son to be absent when his baby was born.

D.Ollie couldn’t bear his son seeing him dying with a broken heart.小题3:The underlined word in Paragraph 3 is closest in meaning to_______.

A.Disappointedly

B.Unwillingly

C.Excitedly

D.Immediately小题4:What can we learn from the passage ?

A.Ollie and his wife had planned to settle in Florida.

B.Ollie cared for his son more than his daughter.

C.Ollie was sad about not being able to see his first grandchild.

D.Ollie died happy and in peace.

判断题