阅读下面材料，在空白处填入适当的内容或括号内单词的正确形式。

It seems recently that more and more of my friends are facing some seemingly unbeatable challenges in their lives. Some have lost their jobs and some have __ 小题1:___ (fail) marriages. All too many have health problems.

I don’t know if it is desperation __小题2:___ causes them to turn to me for advice or whether they have come to value our friendship. But __小题3:___ is difficult to offer words of hope when all they feel is hopeless. They expect answers to get them back __小题4:___ their feet again.

I have often struggled with what to say,  ___小题5:___ (most) because I have faced many of the same challenges in my own life. I remember how empty I felt after someone cheerfully offered words like “Things will get better!”

Now , being thought of __小题6:___ a source of hope or a good example of what to do through printed words, I have even __小题7:___ (many) people contacting me.

So what do I say? “Begin again.”

It sounds too simple, __小题8:___ it is indeed the answer. All life __小题9:___(challenge) bring about an ending and the chance for __小题10:___(begin).

将Zn棒和Cu棒用导线连接后，放入某电解质溶液中，构成如下图所示装置．试回答下列问题：

（1）若电解质溶液为稀硫酸，则Zn棒为原电池的______极，可观察到Cu棒的所产生现象是______，试用电极反应式表示该现象：______．

（2）若电解质为硫酸铜溶液，则Cu棒上发生______反应，Zn棒上发生反应的电极反应式为：______．

（3）若在上述两个过程中，Zn棒减少的质量相等，则Cu棒上（1）和（2）所析出物质的质量之比为：______．