一位同学用如图所示的电路探究“电流与电阻的关系”．电源电压不变，下表是实验数据，若第四次实验时将定值电阻的阻值由30Ω调为40Ω后就直接读出电流表的示数，这个示数应该是（　　）

双曲线$\frac{x^2}{a^2}-\frac{y^2}{b^2}=1$（a＞0，b＞0）的左、右焦点分别为F₁，F₂，P为双曲线右支上一点，PF₂与圆x²+y²=b²切于点G，且G为PF₂的中点，则该双曲线的离心率为（　　）

如图所示，O为杠杆的支点，第一次杠杆在重物G和力F₁的作用下处于水平位置平衡。如果第二次杠杆在重物G和力F₂的作用下仍在图中位置保持平衡，下面关系中正确的是（   ）

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后的词。

注意：1.每处错误及其修改均限一词。2.只允许修改10处，多者（从第11处起）不计分。

Dear Andy,

    I am glad to learn from that you are coming to China and will stay at my home. My parents and I are very pleasing to have you with me. Now let me tell you that we have arranged for you. I know the school would organize a lot of things for you do in the morning. In the afternoon, I'll show you around and take you to some place of interest. We'll mostly stay at home in the evening watch TV, playing games, and meeting people. I'm sure we'll have a wonderful time or enjoy each other's company.

    I'm looking forward to meet you soon.

Yours sincerely,

Zhao Mei