As science developed rapidly in the direction of technology, it supplies man a better and more comfortable 1. Men will be working shorter and shorter hours,2 and housewives will also be able to have more free time. Can you 3 doing housework without a housewife? Scientists believe this will 4 into realities in not very long time, and perhaps during your lifetime house-robots will take 5 of housewives.

    When I 6 this kind of machine with housewives, some 90 percent of them replied 7 “How soon can I buy one?” The other 10 percent said, “I would be terrified to see it8 about my house.” But when I explained to them that it could be turned 9 or stopped, they quickly realized that it was a 10 object.

    In my own 11 we have found that the washing-up machine is regarded as a good12in the room. There's no greater13than to go to bed in the evening and 14 that the washing-up is being done downstairs after we are 15.

    Some families would 16 to have their robot slaves 17 all the downstairs housework after they were in 18 at night, while others would have it19 in the mornings. But this would be entirely a matter of20.

综合回答：妈妈在厨房中用电烤箱，一会后肉香四溢，当打开热水壶烧水时，家中的保险丝熔断了．请你找出一个场景，并用所学物理知识进行解释．____ 

阅读文章，回答文后的问题。

社戏（节选）

    我的很重的心忽而轻松了，身体也似乎舒展到说不出的大。一出门，便望见月下的平桥内泊着一只白篷的航船，大家跳下船，双喜拔前篙，阿发拔后篙，年幼的都陪我坐在舱中，较大的聚在船尾。母亲送出来吩咐"要小心"的时候，我们已经点开船，在桥石上一磕，退后几尺，即又上前出了桥。于是架起两支橹，一支两人，一里一换，有说笑的，有嚷的，夹着潺潺的船头激水的声音，在左右都是碧绿的豆麦田地的河流中，飞一般径向赵庄前进了。

    两岸的豆麦和河底的水草所发散出来的清香，夹杂在水气中扑面的吹来；月色便朦胧在这水气里。淡黑的起伏的连山，仿佛是踊跃的铁的兽脊似的，都远远的向船尾跑去了，但我却还以为船慢。他们换了四回手，渐望见依稀的赵庄，而且似乎听到歌吹了，还有几点火，料想便是戏台，但或者也许是渔火。

    那声音大概是横笛，宛转，悠扬，使我的心也沉静，然而又自失起来，觉得要和他弥散在含着豆麦蕴藻之香的夜气里。

    那火接近了，果然是渔火；我才记得先前望见的也不是赵庄。那是正对船头的一丛松柏林，我去年也曾经去游玩过，还看见破的石马倒在地下，一个石羊蹲在草里呢。过了那林，船便弯进了叉港，于是赵庄便真在眼前了。

根据下列人体内一些液体的正常的pH范围判断，其中，一定能使石蕊溶液变红的是（  ）