一辆汽车 $\frac{3}{5}$ 小时行驶27千米，以同样的速度，这辆汽车 $\frac{1}{5}$ 小时行驶____千米，行驶1千米需要____小时。

There are _____months in a year. _____ month is December.

若式子$\sigma \left(a,b,c\right)$满足$\sigma \left(a,b,c\right)=\sigma \left(b,c,a\right)=\sigma \left(c,a,b\right)$，则称$\sigma \left(a,b,c\right)$为轮换对称式．给出如下三个式子：
①$\sigma \left(a,b,c\right)=abc$；    ②$\sigma \left(a,b,c\right)=a^2-b^2+c^2$；
③$\sigma \left(A,B,C\right)=\cos C·\cos \left(A-B\right)-{\cos }^{2}C$$(A,B,C$是$△ABC$的内角)．
其中，为轮换对称式的个数是（ ）

在测量液体温度的实验时，如图所示的四种方法中正确的是（　　）

完型填空
     Monty was the son of a horse trainer. When he was in his ninth grade, he was asked to write a 1 about what he wanted to be and do when he grew up.
     That night he wrote a seven-page paper saying that someday he’d 2 a horse ranch (牧场). He wrote about his dream in great detail and he 3 drew a picture of a 200-acre ranch with all the buildings.
     He put a great deal of his 4 into the project and the next day he handed it in 5 his teacher. Two days later he received his paper back. On the front page was a large red F with a 6that read, “See me after class.”
     The boy with the dream went to see the teacher after class and asked, “7 did I receive an F?”
     The teacher said, “This is an 8 dream for a young boy like you. You come from a poor family. Owning a horse ranch requires a lot of 9. You have to buy the land. You have to pay for other things. There is no10you could ever do it.” Then the teacher added, “11 you rewrite this paper with a more realistic goal, I will reconsider your grade.”
     The boy went home and thought about 12 long and hard. He asked his father what he should do. His father said, “Look, son, you have to make up your own mind on this. However, I think it is a very important 13 for you.”
     Finally, after sitting with it for a week, the boy turned in the 14 paper, making no changes at all. He said to the teacher, “You can keep the F and I’ll keep my15.”