某种商品期货合约交割月份的确定，一般由其生产、使用、消费等特点决定。( )

以下程序段打开文件后，先利用fseek函数将文件位置指针定位在文件末尾，然后调用ftell函数返回当前文件位置指针的具体位置，从而确定文件长度，请填空。
FILE*myf; long f1；
myf= 【20】 ("test,t","rb");
fseek(myf,(),SEEK_END) ；f1+ftell(myf)；
fclose(myf);
printf("%1d\n",f1);

钢板用两个铆钉固定在支座上，铆钉直径为d，在图示载荷作用下，铆钉的最大切应力是（）。

A.

B.

C.

D.

下列有关票据伪造的表述中，不符合票据法律制度规定的有( )。

A．票据的伪造仅指假冒他人名义签章的行为

B．票据上有伪造签章的，不影响票据上其他真实签章的效力

C．善意的且支付相当对价的合法持票人有权要求被伪造人承担票据责任

D．票据伪造人的伪造行为即使给他人造成损害，也不承担票据责任

当前数据库技术的发展已形成各种类型的数据库应用技术，下列叙述中， ( )是这种发展的推动力。 Ⅰ．应用的驱动 Ⅱ．多种技术与数据库技术的结合 Ⅲ．关系数据库的研究基础

A．Ⅰ

B．Ⅱ

C．Ⅰ和Ⅱ

D．全都是

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.