6500千克=______吨______千克．

1+2-3+4+5-6+7+8-9+…+601+602-603+604+605-606．

A、B、C为黑箱上的三个接点，最多只能接两个电学元件。为探明其结构，某同学用多用电表进行测量。

（1）用直流电压挡测量：A、B、C三点间均无电压，则盒内三点间是否接有电源？答：          。

（2）用欧姆表进行测量，测量的阻值记录如下表：

红表笔	A	C	C	B	A	B
黑表笔	C	A	B	C	B	A
阻值	有阻值	阻值与AC间测量值相同	很大	很小	很大	接近AC间阻值

则盒内的电学元件是           和           。

（3）在虚线框内画出盒内元件的符号和电路。

无土栽培的实验证明了下列哪一项不是植物生长所必需的[ ]

A．阳光

B．无机盐

C．水分

D．土壤

在不改变企业经营方向的前提下，不宜降低成本总额，而应通过提高产品产量，降低其单位额的成本项目是（）。

A.新产品开发费

B.机器设备折旧费

C.员工培训费

D.保险费

E.管理人员薪金

While the ripples of America’s subprime-mortgage crisis have spread far and wide, Latin America—a place long associated with financial disaster—has remained improbably calm. Banks have reported no unpleasant surprises. Brazil and Peru have been blessed with coveted investment-grade ratings. Surprisingly, perhaps the fleetest country of all has been Argentina. Since it emerged from the financial crisis of 2001-02, it has been one of the world’s fastest-growing economies. It is expected to expand faster than most of its neighbors again this year.

Quite simply, it barely has any credit. Back when its economy virtually collapsed, the country suffered a run on its banks, followed by a freeze on withdrawals, and a massive currency devaluation. As a result, bank lending to the private sector shrivelled, from 23.8% of GDP in 2000 to 10.8% in 2003. Since then, it has rebounded to a piddling 13% ; by contrast, the ratio in Brazil was 36.5% in 2006. Almost all of these loans in Argentina are accessible only on a short-term basis.

Once its recovery began in June 2002, Argentina became a paradise for business. Unemployment of over 20% kept wages down, and the devaluation gave exporters an edge on foreign competitors. The ample productive capacity left idle by the crisis meant firms could expand without making big investments. And the windfall profits reaped by agricultural exporters, thanks to record commodities prices, enabled many of them to finance new projects out of earnings. Hence the economy could grow at almost 9% a year with little need for credit.

But such a lucky confluence of factors could not last. Starting in early 2005 ,.inflation picked up, a sign that the installed capacity was starting to limit output. Salaries and prices for raw materials increased sharply, cutting into profits. And farmers were particularly hard hit when the government nearly doubled the taxes in farm exports. Now, just as companies need to embark on big investments if they are to keep growing, their margins are no longer big enough to pay for the expansion and they need to borrow.

So, the time is ripe for the country’s financial system to recover. But a number of things are in the way. Foremost is Argentina’s business risk. Those in the informal economy (which represents over 40% of GDP) can neither save nor borrow legally, lest they become known to the taxmen. The rest remain cowed by memories of the crisis. Although Argentines have poured their savings into property, fuelling a construction boom, they still hold about four-fifths of their deposits abroad.

Inflation, fuelled by a public-spending binge, state-mandated wage increases, and a cheap currency, is not helping either. No one knows how high it is. The consumer-price index is doctored to keep the official rate below 10%, but private estimates suggest it is near 25%. Without a reliable index of inflation, lending is almost impossible, even for the medium term. And the central bank has kept interest rates ply negative in real terms, encouraging workers to spend their wages rather than to save.

what is the main idea of the text（）

A. Credit does not play a role in economy

B. Banking sector and capital markets sometimes are not so important in economy

C. Argentina’s economy is the best one in Latin America

D. Argentina is a paradise for business