| The explosion of a star is an awesome
event. The most violent of these cataclysms, which produce supernovae, probably
destroys a star completely. Within our galaxy of roughly 100 billion stars the
last supernova was observed in 1604. Much smaller explosions, however,
occur quite frequently, giving rise to what astronomers call novae and dwarf
novae. On the order of 25 novae occur in our galaxy every year, but only
two or three are near enough to be observed. About 100 dwarf novae are known
altogether. If the exploding star is in a nearby part of the galaxy, it may
create a "new star" that was not previously visible to the naked eye. The last
new star of this sort that could be observed clearly from the Northern
Hemisphere appeared in 1946. In these smaller explosions the star loses only a
minute fraction of its mass and survives to explode again. Astro A. Cataclysmic Variables B. Miracles in the Skies C. Exploding Stars D. New Stars [单选题]消防装备用燃料有( )。(易)
A.可溶燃料 B.气体燃料 C.固体燃料 D特殊燃料 [判断题]2.47 注册登记查验发动机（驱动电机）号码时，应实车查看打刻（或铸出）的发动机（型号和出厂编号，核对是否与机动车整车出厂合格证明、货物进口证明书等凭证一致，确认发动机号码有无被凿改等嫌疑。如打刻（或铸出）的发动机型号和出厂编号不易见，只查看发动机易见部位或覆盖件上能永久保持的标有发动机型号和出厂编号的标识。
A.正确 B.错误 [单项选择]女性，26岁。以急进性肾炎综合征势态起病，肾活检报告为急进性肾炎Ⅰ型（）
A. 细胞免疫介导 B. 抗肾小管刷状缘抗体介导 C. 原位形成免疫复合物介导 D. 循环免疫复合物介导 E. 抗肾小球基膜抗体介导下列肾炎的发病机制是 [填空题]双线电气化区段发生断杆、断线影响邻线列车运行时，应（）邻线列车。
[单项选择]慢性粒细胞白血病的血象特点是
A. 白细胞分类原始、早幼粒细胞明显增多 B. 红细胞大小不等，中心淡染 C. 血小板增多 D. 白细胞计数一定高于正常 E. 白细胞分类以中幼粒以下阶段细胞明显增多为主 [判断题]各单位原则上应取消现金结算。( )
A.正确 B.错误 [单项选择]采用绝缘铜芯线作保护接地线或保护接零线，最小截面积为（）平方毫米。
A. 1.5 B. 2.5 C. 4 [简答题]写出Excel常用函数名及其功能(写出4种即可)。
我来回答: 提交
|
