— Only________ people can afford to travel around the world.
—Not exactly. I heard that a poor student travelled around the world with little money.
A:rich
B:poor
C:strong
设函数f(x)=xm+ax的导数f′(x)=2x+1,则数列1f(n) n∈(N*)的前n项和( )
连词成句
根据课文《画杨桃》内容填空。