锯割时，工件夹持距钳口较远会怎样（）？A、锯割时产生噪音 B、节省体力 C、便于起锯

The fridge is considered a necessity. It has been so since the 1960s when packaged food first appeared with the label: "store in the refrigerator. "
In my fridgeless fifties childhood, I was fed well and healthy. The milkman came daily, the grocer, the butcher, the baker, and the ice cream man delivered two or three times a week. The Sunday meat would last until Wednesday and surplus bread and milk became all kinds of cakes. Nothing was wasted, and we were never troubled by rotten food. Thirty years on, food deliveries have ceased, fresh vegetables are almost unobtainable in the country.
The invention of the fridge contributed comparatively little to the art of food preservation. A vast way of well tried techniques already existed—natural cooling, drying, smoking, salting, sugaring, bottling…
What refrigeration did promote was marketing—marketing hardware and electricity, marketing soft drinks, marketing dead bodies of animals around the globe in search of a good price.
Consequently, most of the world’s fridges are to be found, not in the tropics where they might prove useful, but in the wealthy countries with mild temperatures where they are climatically almost unnecessary. Every winter, millions of fridges hum away continuously, and at vast expense, busily maintaining an artificially cooled space inside an artificially heated house—while outside, nature provides the desired temperature free of charge.
The fridge’s effect upon the environment has been evident, while its contribution to human happiness has been insignificant. If you don’t believe me, try it yourself, invest in a food cabinet and turn off your fridge next winter. You may miss the hamburgers, but at least you’ll get rid of that terrible hum.

Why does the author say that nothing was wasted before the invention of fridges

A．People would not buy more food than was necessary.
B．Food was delivered to people two or three times a week.
C．Food was sold fresh and did not get rotten easily.
D．People had effective ways to preserve their food.

测定食品中有机氯农药残留量，国标规定用气相色谱法，其检测器是（）

A.FID

B.FPD

C.NPD

D.ECD

E.TCD

资产负债表中的“应付账款”项目，其填列方法是( )。

A．根据“应付账款”科目的期末贷方余额和“应收账款”科目的期末借方余额计算填列

B．直接根据“应付账款”科目的期末贷方余额填列

C．根据“应付账款”科目的期末贷方余额和“预收账款”科目的期末借方余额计算填列

D．根据“应付账款”科目和“预付账款”科目所属相关明细科目的期末贷方余额计算填列

在我国抗震设防烈度（）度以上地区公用电信网中使用交换、传输、通信电源、移动基站等主要设备，应取得信息产业部颁发的通信设备抗地震性能检测合格证。

A.6

B.7

C.8

D.9

因为承包某工程项目需要，甲建筑工程公司与乙建材供应公司签订一份建材购销合同，合同约定：乙公司将位于某地仓库内的水泥100t卖给甲公司，单价500元/t。同时双方又签订一份仓储合同，由乙公司负责为甲公司保管这批水泥直至该项目结束，某晚，乙公司的仓库遭雷击起火，在救火过程中甲公司的水泥被淋湿50t，工作人员将剩余的水泥清理出来堆放在院子中就各自回去睡觉了。夜里，天降暴雨，剩余50t水泥全被冲毁。根据我国《合同法》的规定，下列说法正确的是( )。

A．乙公司因不可抗力违约不应承担违约责任

B．乙公司应承担因救火被淋湿的50t水泥的赔偿责任

C．乙公司应承担因暴雨被冲毁的50t水泥的赔偿责任

D．乙公司应承担全部100t水泥的赔偿责任