读图1—13地震波速度与地球内部构造图，回答：

增加：在缺词处加一个漏字符号(∧)，并在其下面写出该加的词。

删除：把多余的词用斜线（\）划掉。

修改：在错的词下划一横线，并在该词下面写出修改的词。

注意：1).每处错误及其修改均仅限一词；

2).只允许修改10处，多者(从第11处起)不计分。

    The American TV show The Voice is one of my most favorite amusement shows. In one hand, I can listen to different styles of music. On the other hand, I can see the singers' stories, who are so inspiring. I was deeply impressed by a musical boy who was from the countryside. If he was very young, he loved to sing while doing the farm work. After work, he learned to play guitar. He liked living on the farm, for the life was simple. The boy brought his guitar to the stage, worn a fashionable hat which made him seem so mysteriously. When the boy sing a song with the guitar, all the judge were astonished by his talent. As a result, he won the game but finally became famous throughout the country.

下列动物中哪一种是我国特产的珍稀哺乳动物（　　　）

定值电阻R₁和R₂串联后，接在电压可调的电源两端，电路中的电流I随电源电压U变化关系的图像如图所示。已知R₁=4Ω，则R₂=____ Ω。