题干

如图所示,相同的水下录音装置A、B录下在海里同一位置的鲸发出的同一段声音.A录到的有高、低音,B录到的只有低音,由此可以推测;在海洋中能传播较远距离的声音是(  )

A:频率较低的

B:音调较高的

C:能量较小的

D:响度较小的

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答案(点此获取答案解析)

A

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    Six years ago, I walked into a local animal shelter on a cold, rainy day.1my house was already full of cats and dogs, I still couldn't 2an occasional visit to the shelter. This time as I was walking down the row of pens(畜栏) full of barking dogs, I3a small boy looking into one of them.

    He had a malnourished(营养不良的)looking body and a4face with a big nose5out of the middle of it. He was looking at a small golden dog. Its ribs(肋骨)were showing and its thin tail was folded between its legs. It wasn't begging for6like the other puppies7was hiding in the corner instead. The boy looked up at me with8eyes and asked what was wrong with it. “It was probably abused and9 ” I said. “That is why it is so 10 ”

    The boy 11turned to an old lady and said, “ Grandma, I want this one.” The old woman smiled and walked to the front desk to fill out the 12forms. I followed her and asked 13the boy. She told me that he'd had a 14start in life, too. She had just gotten custody(监护权) of him15the state had taken him from his parents. She hoped getting a dog would make his life 16for him. I looked back at him, holding his scared puppy, and said a prayer for them both.

    It was yesterday that I was driving down the road enjoying a gloriously sunny, spring day. Then in a green front yard I saw the boy. His 17body was tall and strong. His nose no longer 18big but fit well into his smiling face. He was throwing a ball to a healthy, happy dog shining golden hair. His little act of love and 19had indeed gone a long way. It had saved a dog's life, 20his own heart, and given this middle-aged man fresh hope for the whole world.