用数学归纳法证明“1+$\frac{1}{2}+\frac{1}{3}+\cdots$+$\frac{1}{2^n-1}$＜n（n∈N^*，n＞1）”时，由n=k（k＞1）不等式成立，推证n=k+1时，左边应增加的项数是（　　）

B

    Do you like reading stories? Maybe you will answer, "No, I am not a child any more!" Yes, children all over the world always love stories.

    Chinese children are 1 in Monkey King's story. It 2 a popular bedtime story in China for many years. In fact, adults also love the story a lot. For them, Monkey King has become a very 3 part in the memory of their childhood. The clever and humorous monkey 4 the hearts of many Chinese people. British boys and girls all know Alice's Adventures in Wonderland well. As the name shows, it's a story full of dangerous but exciting trips. Children 5, cry and even get frightened(害怕的) with Alice together while reading the story. Most American kids have read The Adventures of Tom Sawyer, by the famous 6, Mark Twain. Everyone likes the brave boy who also has lots of 7. Some scenes(场景) of the story may make your heart go faster, for Tom and his friends meet some very bad men and are usually 8. Of course in the end, they beat the bad ones.

    You may also ask me 9 I like stories. Yes, I have liked them since I was very young. At that time, I often 10 all my pocket money on story books. For me, stories are much more delicious than chocolate! They help me learn a lot. So either young or old, let's enjoy stories.

分别装有相同的质量的水、盐水、酒精的三个相同容器中液面高低如图．已知ρ_盐水＞ρ_水＞ρ_酒精，则甲液体是 ____，乙液体是 ____，丙液体是 ____