首页
登录
职称英语
The great advance【C1】______rocket theory 40 years ago showed that liquid-fue
The great advance【C1】______rocket theory 40 years ago showed that liquid-fue
游客
2025-01-22
17
管理
问题
The great advance【C1】______rocket theory 40 years ago showed that liquid-fuel rockets were far【C2】______in every respect to the skyrocket with its weak solid fuel, the only kind of rocket then known.【C3】______, during the last decade, large solid-fuel rockets with【C4】______fuels about as powerful as liquid fuels have【C5】______their appearance, and it is a favorite layperson’s question to【C6】______which one is "better". The question is meaningless.【C7】______might as well ask whether a gasoline or a diesel engine is "better". It all【C8】______on the purpose. A liquid-fuel rocket is complicated,【C9】______has the advantage that it can be controlled beautifully. The burning of the rocket engine can be stopped completely; it can be reignited when【C10】______.【C11】______, the thrust can be made to vary by adjusting the speed of the fuel pumps. A solid-fuel rocket, on the other hand, is rather【C12】______in construction,【C13】______hard to build when a really【C14】______size is desired. But once you have a solid-fuel rocket, it is ready for action【C15】______very short notice. A liquid-fuel rocket has to be fueled first and cannot be【C16】______readiness for very long after it has been fueled.【C17】______, once a solid-fuel rocket has been ignited, it will keep burning. It cannot be stopped and reignited【C18】______desired(it could conceivably be stopped and reignited after a pre-calculated time of burning has e-lapsed. and its thrust cannot be varied. Because a solid-fuel rocket can be kept ready for a long time, most military missiles【C19】______solid fuels, but human-piloted spaceflight needs the fine adjustments that can【C20】______be provided by liquid fuels. [br] 【C20】
选项
A、not
B、all
C、enough
D、only
答案
D
解析
前文已经提到液体燃料火箭有操作起来得心应手的优点,所以此处所说的可以有细微调节功能的人类驾驶的航天飞机必定是液体燃料提供助力。
转载请注明原文地址:https://tihaiku.com/zcyy/3923293.html
相关试题推荐
Astechnologicaladvancesputmoreandmoretimebetweenearlyschoollifeandt
Hewaslookingimpatientatthevisitingsalesman,whoshowednosignsofgettin
Thegreatadvance【C1】______rockettheory40yearsagoshowedthatliquid-fue
Thegreatadvance【C1】______rockettheory40yearsagoshowedthatliquid-fue
Thegreatadvance【C1】______rockettheory40yearsagoshowedthatliquid-fue
Thegreatadvance【C1】______rockettheory40yearsagoshowedthatliquid-fue
Thegreatadvance【C1】______rockettheory40yearsagoshowedthatliquid-fue
Thegreatadvance【C1】______rockettheory40yearsagoshowedthatliquid-fue
Thegreatadvance【C1】______rockettheory40yearsagoshowedthatliquid-fue
Thegreatadvance【C1】______rockettheory40yearsagoshowedthatliquid-fue
随机试题
[originaltext]BadweatherforcedmissionmanagerstopostponelaunchingNASA
[originaltext]W:GregorywillbeleavingthisSundayandit’salsohisbirthday
下列技术经济指标中,属于公共建筑设计方案的技术经济指标的是( )。A.体型系数
女性,30岁,Ⅰ型糖尿病病史10年,长期饮食控制及胰岛素治疗,血糖控制可。出现反
高脂肪、高糖含量的食物有害人的健康。因此,既然越来越多的国家明令禁止未成年人吸烟
李某购买的商品房交付后,经检测室内空气质量不符合国家标准。预计李某治理空气污染的
生活好了,人们越来越喜欢外出旅游度假。但在旅游中应当如何注意个人行为、体现旅游文
一般资料:某男,25岁,初中毕业,车工,目前已病休1年。 案例介绍:5年前在车
(2021年真题)甲公司职工钱某在上班期间因操作失误致使手臂损伤而住院治疗。下列
在我国,纳入政府非税收入管理的财政资本有( )。A.彩票公益金 B.行政事业性
最新回复
(
0
)