要求：有针对性，有条理，切实可行。字数不超过350字。

4和8都是16的[ ]

A．因数

B．倍数

C．偶数

D．合数

因特网是一个庞大的计算机网络，每一台入网的计算机一般都分配有一个IP地址。下面关于IP地址的叙述中，正确的是______。
①72.259.5.0可以作为一个IP地址
②每一台上网计算机的IP地址都是惟一的
③一台机器的IP地址可以用它的主机名代替
④IP地址由类型号、网络号、主机号3个部分组成

A．①②④正确

B．②③④正确

C．只有②④正确

D．都正确

党的十八届五中全会提出的共享发展理念，其内涵主要包括（）等方面。

A.全民共享

B.全面共享

C.共建共享

D.渐进共享

On Saturday August 12, 2000, during Northern Fleet training exercises in the Barents Sea, the Russian nuclear submarine Kursk sank in about 100 meters of water with some 118 sailors aboard. It’s known later that several officers were also aboard, observing the training exercises. The Kursk is lying on the ocean floor in the Barents Sea. The Russian Navy said that it was listing 30 degrees to port. Other sources reported it Was listing as much as 60 degrees. According to a Russian newspaper, when the submarine Kursk failed to make contact with the naval command at the right time later that day, Northern Fleet Commander Admiral Vyachesav Popov ordered rescue ships into the area. It took hours to find the submarine, as it didn’t launch a marking buoy before sinking.

Russian Navy Chief insisted that the submarine Kursk had been involved in a major collision, but a great deal of information shows that this is not true. Up till now, it’s believed that an explosion in the torpedo compartment in the nose of the Kursk was the likely cause. Now Russian government officially asked Norway for help in recovering of sailors’ bodies first of all, and Norway has agreed to offer all help. But Russian insisted that only Russians work inside the submarine Kursk and that the work last for about 10～18 working days. It is expected to recover only 25～35 bodies from the Kursk.

It was not until October 25, when a team of Russian divers entered the submarine Kursk, some 350 feet below the surface, that truth became clear. On November 7, in the morning, owing to the icy and the cold weather, a special rescue meeting held on Murmansk decided to stop the whole bodies recovering operation.

Why did Russia insist that only Russian divers can work inside the submarine Kursk（）

A. Because the Barents Sea is very icy and the weather is too cold.

B. Because Russia feared that the top secrets inside the Kursk will be let out.

C. Because Russian divers are much more skilled than those from Norway.

D. Because Russian government wants to bring the cost down to the lowest degree.