根据材料内容，选择正确答案。

    Tom went to see his grandparent with his father. In the train Tom often put his head out of the window. His father said, "Tom, don't put your head out of the window." But Tom went on putting his head out of the window.

    His father took Tom's hat quietly and hid it behind his back and said to Tom, "You see your hat is gone." Tom was afraid. His father said, "Well, whistle(吹口哨) once. Maybe your hat will come back." Tom whistled. His lather put his hat on Tom's head quickly. "Oh! It's wonderful!" Tom laughed and said. He quickly took his father's hat and threw it out of the window. "Now it's your turn to whistle, Dad!" he said happily.

写作

某英文报举办“家乡的变化”主题征文活动。请你根据下表的提示，以“The Changes in My Hometown” 为题，用英语写一篇100词左右的短文。标题和开头已给出，不计入总词数。

The Changes in My Hometown

My hometown has changed a lot over the years. ……

一个电流表的满偏电流I_g＝1 mA，内阻为500 Ω，要把它改装成一个量程为10 V的电压表，则应在电流表上(  )