航线规划一般分两步:首先是飞行前()其次是飞行中() A.预先规划,在线规划 B.预

题型:单项选择题

问题:

航线规划一般分两步:首先是飞行前()其次是飞行中()

A.预先规划,在线规划

B.预先规划,实时规划

C.预规划,重规划

考点:无人机AOPA驾驶证考试无人机培训综合练习无人机培训综合练习题库
题型:单项选择题

在一个细胞周期中,可能发生在同一时期的变化是[ ]

A.DNA复制和中心粒复制

B.染色体加倍和染色单体形成

C.细胞板出现和纺锤体出现

D.着丝点分裂和同源染色体分离

题型:单项选择题

男性,18岁。因左侧脓胸行胸腔闭式引流术3个月,现已无引流液。查体:左胸廓塌陷,肋间隙变窄。X线胸片:肺内未见明显病变。

患者拒绝住院,1个月后出现右侧颜面无汗、上眼睑下垂、瞳孔缩小、眼球内陷。复查X线胸片:右肺顶部致密块影。最可能的诊断是()

A.转移性肺癌

B.周围型肺癌

C.中央型肺癌

D.肺不张

E.原发性肺结核

题型:单项选择题

对本班没有进行工作的工作面可以不安排检查瓦斯。

题型:单项选择题

根据短文内容,从短文后的选项中选出能填人空白处的最佳选项。选项中有两项为多余选项。

                                                                The Mississippi

     The Mississippi is a great river whose relationship with man goes way back beyond its discovery in the

16th century. The River Indians used it as a highway and as a source of food, and it was they who gave it

its name-"misi" meaning "great" and "sipi" meaning "water". When the length of its branch, the Missouri, is

added to it, the Mississippi becomes greater. 1_____. From the source of the Missouri to the tip of the delta

(三角洲), it is 2480 miles long.

     Great rivers are likely to suffer floods. In 1927 the Mississippi flooded 26 thousand acres, sweeping

away farms, towns, everything in its path. In 1938 its floods drowned or killed 200 people and made millions

homeless. Today the river has largely been controlled. 2_____.

     Industries have spread down some of the waterways of the delta, but otherwise the delta is a remote place,

the homeland of a little colony of French Canadians that the British drove out of Nova Scotia in the 18th

century. They still speak French, mixed with English, Indian, Spanish and Negro idioms. They keep to

themselves, farming the rich soil of the delta. 3_____. 

     4_____. Pioneers who first reached its banks wondered not only where it went, but what lay beyond. In

1764 the French founded a city on the right bank of the river, and named it after their king, Louis XV. This

city, named St. Louis, became the jumping-off place for the adventurous men and women who opened up

the Great Plains, and the way to the Far West.

     Some 40 years earlier, at the beginning of the 18th century, the French had founded another city just above

the Mississippi delta, New Orleans. 5_____. New Orleans is one of the great ports of the world, and one of

the greatest terminals for both sea and river traffic.

A. It was the Mississippi that made the city what it is

B. Levees, high banks built of earth, hold back the flood waters

C. Therefore, as we know, it's the third longest river in the world

D. It is known that the "Great Water" has also been a frontier river

E. However, they paddled up and down the Mississippi in their boats to seek their fortune

F. The "Great Water" always remains a thread, for the streets of the city are below the'level of the river

G. They call themselves Cajuns, who have actually been leading fairly primitive lives and preserving their own

     traditions

题型:单项选择题

已经老化的橡皮管应立即停止使用

更多题库