某棉纺织厂（cotton mill）的防治联合厂房，在×风机的前端设置×空7-9气逬行净化处理。×过滤后的空气循环使用，×空气中的含尘浓度低于其爆炸下限（）

The cotton mill （棉纺厂) will be much more productive if it is properly（).

A.manages

B.manager

C.managing

D.managed

state of___________.

A. Rhode Island

B. New York

C. Connecticut

D. Georgia

ticeship in an English spinning mill, he was apparently so worried about the growth, and hence saturation, of the industry in the United Kingdom that, in 1789, without the knowledge of his family, Slater traveled to America at the age of 21. This was done in secret; it was illegal at the time to export anything to the U.S. relating to machinery, including engineers. Also, the U. S. was offering rewards for textile information.

Arriving in New York, it was not long before he learned of the experimental work of Moses Brown and William Almy, in Pawtucket, with more advanced machines than the Spinning Jennys used in New York. Initially without any contract, and working alongside the engineers already employed at the Almy and Brown mill, Slater successfully reworked a spinning frame. along the lines of Arkwright's Water Frame. This three months of work resulted in a partnership with Almy and Brown. He understood the whole spinning process and knew which machines were vital to overall success of a mill.

However, that management training and knowledge really came into its own over the next two years as Slater labored to educate the embryonic textile industry and businessmen in the techniques that had proved so successful in Belper. Without these, Slater believed the industry would not flourish. In particular, his aim was to maximize the output from the machinery and develop the market place in order to sell all the yarn that could be produced. Prior to this, the philosophy of Almy and Brown was to produce only to order. By 1792, Slater had proved, through the use of his Belper-learned management techniques, that he could make spinning a profitable business. This led to building the Old Slater Mill—the first successful U. S. cotton spinning mill. Slater's view was to concentrate on a specific aspect and specialize. The other partners believed in covering the whole textile process through to finished goods, including knitting. As a result, in 1797, Slater broke away and built his own larger mill—the White Mill. Following the success of Slater's business, the cotton industry really took off and over the next ten or so years, over eighty mills developed. Slater has been called both the "Father of American Industry", and the "Founder of the American Industrial Revolution".

What does the second paragraph mainly discuss？

A．Slater's arrival in America.

B．New York and the Almy and Brown mill.

C．The first three months and achievement of a partnership.

D．Slater's understanding of the spinning process.

A.纺纱车间

B.织布车间

C.整包车间

D.印染车间

E.供电车间

F.机修车间

中的含尘浓度低于其爆炸下限（）。

A.15%

B.25%

C.50%

D.100%

A.15%

B. 20%

C.25%

A.15％

B.25％

C.50％

D.75％

A.合理

B.不合理

C.依据实际情况而定

D.不能确定

使用，应使空气中的含尘浓度低于其爆炸下限的（）

A.15%

B.25%

C.50%

D.100%

A.15%

B.25%

C.50%

D.100%