Earth has an atmosphere. The atmosphere protects us from harmful rays. What is the atmosphere made of? A. Water vapor B. Gases C. Soil D. Rocks 相关知识点: 试题来源: 解析 B。解析:地球有大气层,大气层保护我们免受有害射线的伤害。大气层是由气体组成的。选项 A 水蒸气只是大气层的一部分...
The atmosphere protects the earth. What is the atmosphere made of? A. Gas and dust B. Water and fire C. Earth and moon D. Stars and gas 相关知识点: 试题来源: 解析 A。本题考查对大气层组成的了解,大气层由气体和尘埃组成。B 选项水和火不对;C 选项地球和月亮不对;D 选项星星和气体不对...
The atmosphere of the Earth begins with the Earth's surface and extends to the boundary with outer space. Although there is no clear point at which the atmosphere ends and outer space begins, the atmosphere itself is usually divided into five different layers: the troposphere, the stratosphere,...
We believe they gradually spiral down out of the rings and into the planet's atmosphere. This occurs as a result of the planet's gravity, and also because of the effects of its magnetic field. Now, if material from Saturn's rings is being lost and nothing new is added from time to ...
So could it be that Earth really is unique? All living things on Earth are made of the same building blocks, long carbon-based molecules.所以地球真的是独一无二的吗？地球上所有的生物都有着相同的组成成分，即长碳基分子。Scientists now think that a large proportion of these molecules came from...
The inner ear is a network of channels containing fluid that moves in response to sound or movement. To perform the function of hearing, the ear converts the energy of pressure waves moving through the air into nerve impulses that the brain perceives as sound. Vibrating objects, such as ...
The inner ear is a network of channels containing fluid that moves in response to sound or movement. To perform the function of hearing, the ear converts the energy of pressure waves moving through the air into nerve impulses that the brain perceives as sound. Vibrating objects, such as ...
Earth it is a minor constituent.But there is an enormous amount of this compound buried in the sedimentary rocks of Earth's crust, enough so that, if it were all released, our atmosphere would be much more like those of our neighboring planets.How did carbon dioxide gas end up in the ...
What would happen if the Earth ran out of food and water? So, the good news is Earth isn’t going to run out of water anytime soon. The water we have doesn’t exactly do a disappearing act, it just changes st...
B)It has a growing number of newly coined words, C)It can be easily picked up by overseas travellers. D)It is the largest among all languages in the world. Conversation 2 12.A)To return some goods. B)To apply for a job. C)To place an order. ...