化简求值：(1x+1+1x-1)•x2-1x2+3x，其中x=3．

脑脊液检查的适应证是（）。

A.颅后窝有占位性病变

B.中枢神经系统有脑干症状

C.颅内压增高伴视 * * 水肿

D.中枢神经系统的炎症、出血、肿瘤

E.全身衰竭的病人

Christmas is long gone. and Valentine’s Day is a distant memory. That means it's a slow time for jewelers, and a good time for you to make a purchase. Whether you’re out shopping for gold, or silver, here fife a few things you need to know:

What determines price?

The purity of the metal is one of the elements that determines the price. Gold purity is indicated with a stamp of 10K, 14K, 18K, or 24K. And different countries have their own standards. For example, for a piece to be considered gold in the US, it must be at least 10K. In Britain and Canada: 9K. In Italy and France: l 8K. Anything over l 8K is really too soft for everyday wear. That’s why jewelry stores in the US sell mostly 14K.

How much can you expect to pay?

That depends on the weight of the metal and the gemstone(宝石). So keep that in mind, especially when buying online. To keep yourself from getting ripped off, ask yourself the following:

●How long has the company been around?

●What is its return policy?

● Is the jewelry featured on the website visible from all directions?

● Is the company transparent with the gram weights and the size of the gemstones?

Yellow gold? White? Rose?

Yes, it's confusing, and while this is largely a personal decision, there fife a few things to keep in mind. For starters. white or rose gold costs about l 0% more than yellow gold. If you want the “look for less”, consider gold. plated jewelry. “Gold plated” and “gold overlay” mean the same thing and guarantee a thicker layer of finish than “vermeil” which is a flash finish that is thinner and less consistent, but more affordable. Buy vermeil finished pieces you want for a season or two just to follow the fashion. For pieces you want to wear for a lifetime, solid gold is best.

What about sterling silver(标准纯银)?

Sterling silver has been。an alternative for white gold during the difficult economy, and while it used to be more popular with just the younger these days it has much more mass appeal. So much so that retailers are now offering fine gemstones with silver--something you used to see only with gold.

Keep in mind that in the US. the sterling silver standard is 92.5% real silver. Don’t buy it if there isn’t a “925” stamp on it. And keep in mind that the lower price you’re paying for silver means more maintenance. To keep silver jewelry from becoming less shiny, consider keeping a piece of chalk in your jewelry box.

小题1:According to the passage, the underlined phrase “getting ripped off” in Paragraph 3 probably means “_______”.

A．being charged

B．being cheated

C．being affected

D．being attracted小题2:Which of the following is relatively good for only wearing a short time?

A．A 14K necklace.

B．A gold-plated ring.

C．A vermeil ear ring.

D．A gemstone necklace.小题3:We call infer from the last paragraph that silver jewelry should be kept ________

A．in a dry place

B．in a cold place

C．in a wet place

D．in a hot place小题4:The author writes the passage mainly to ________.

A．encourage young people to buy fashionable jewelry

B．tell people the best time to purchase gold and silver

C．introduce the real value and popularity of gold and silver

D．inform people of the factors to consider in buying jewelry

相关系数的假设检验可选用（）

A.散点图直接观察法代替

B.t检验

C.F检验

D.χ²检验

E.以上均可

A公司从B公司融资租入—条生产线，其原账面价值为430万元，租赁开始口公允价值为410万元，按出租人的内含利率折现的最低租赁付款额的现值为420万元，最低租赁付款额为500万元，发生的初始直接费用为10万元。则在租赁开始日，A公司租赁资产的入账价值、未确认融资费用分别是( )。

A．420万元和80万元

B．410万元和100万元

C．410万元和90万元

D．430万元和80万元

一个单位是否单独设置会计机构，往往取决于（ ）。

A．单位规模的大小

B．经济业务的繁简

C．财务收支的繁简

D．经营管理的要求