如图甲是一种恒温调奶器，可以自动调试好加水的奶粉，然后加热到最适合宝宝饮用的温度40℃，还可以自动保温，特别适合夜间使用．图乙是机器的参数表及电路简图（R₁、R₂为电热丝，S为双触点自动开关，接“1”挡时不工作）．求：

型号	HY110M
电源	220V  50Hz
加热功率	500W
保温功率	16W

阅读下列短文，从下面每小题的A、B、C、D四个选项中选出最佳选项。

B

    A group of children meet in the library each week during lunchtime. They are famous as the Miss Margaret Fan Club. Every Thursday, the twelve members of the Miss Margaret Fan Club make their way to the study center in the back of the library.
    The first Thursday they met, Miss Margaret greeted them with a little talk.
    "Welcome to the first meeting of the writing club!" she said. "During the school year, we will meet here to work on story writing. At the end of the year, I will put all of your stories together in a book."
    Miss Margaret gave a pencil and two pieces of paper to each student.
    "Now, your first homework is to think of a character. Now, try to think about an interesting person. When you think of this person, write down all the details(细节)about him or her in your head. "

在探究“平面镜成像特点”的实验中，装置如图甲所示．

在$-2$，$\sqrt{4}$，$\sqrt{2}$，$3.14$， $\sqrt[3]{-27}$，$\frac{\mathrm{\pi }}{5}$，这$6$个数中，无理数共有(        )

下列物态变化过程中，属于汽化的是（  ）