篮球运动员在比赛中每次罚球命中得1分，罚不中得0分，已知某运动员罚球命中的概率为

通过X线表现就能确诊的牙源性肿瘤是（）

A.牙源性角化囊性瘤

B.成釉细胞瘤

C.牙瘤

D.颌骨中央性癌

E.含牙囊肿

通常情况下，一个外中断服务程序的第一条指令是STI，其目的是( )。

A．开放所有屏蔽中断

B．允许低一级中断产生

C．允许高一级中断产生

D．允许同一级中断产生

霍乱毒素每个毒素分子含有1个A亚单位和几个B单位（）。

A.1～3

B.2～4

C.3～5

D.5～7

E.4～6

Vienna was one of the music centers of Europe during the classical period, and Haydn, Mozart, and Beethoven were all active there. As the (1) of the Holy Roman Empire (which included parts of present-day Austria, Germany, Italy, Hungary, Czech and Slovakia), it was a (2) cultural and commercial center (3) a cosmopolitan character. Its population of almost 250,000 (in 1800) made Vienna the fourth largest city in Europe. All three (4) masters were born elsewhere, but they were (5) to Vienna to study and to seek (6) . In Vienna, Haydn and Mozart became close friends and influenced each other’s musical (7) . Beethoven traveled to Vienna at sixteen to play for Mozart; at twenty-two, he returned to study with Haydn.

Aristocrats from all over the Empire spent the winter in Vienna, sometimes bringing their private (8) . Music was an important part of court life, and a good orchestra was a (9) of prestige. Many of the nobility were excellent musicians.

Much music was heard in (10) concerts where aristocrats and wealthy commoners played (11) professional musicians. Mozart and Beethoven often earned money by performing in these intimate concerts. The nobility (12) hired servants who could (13) as musicians. An advertisement in the Vienna Gazette of 1789 (14) : " Wanted, for a house of the gentry, a manservant who knows how to play the violin well. "

In Vienna there was also (15) music, light and popular in (16) . Small street bands of wind and string players played at garden parties or under the windows of people (17) to throw (18) money. Haydn and Mozart wrote many outdoor entertainment (19) , (20) they called divertimentos or serenades. Vienna’s great love of music and its enthusiastic demand for new works made it the chosen city of Haydn, Mozart and Beethoven.

4（）

A.great

B.brilliant

C.unique

D.classical

关于获得性膜下列哪项是错误的：（）

A、其数量与龋病发生呈负相关

B、作为扩散屏障，对釉质面起修复和保护作用

C、影响菌在牙面粘附

D、作为细菌代谢的底物和营养来源