题目内容（请给出正确答案）

[单选题]

It is called solar cooker, a newly designed cooking device and there are many kinds o

A.convenient

B.available

C.useful

查看答案

如果结果不匹配，请联系老师获取答案

您可能会需要：

重置密码查看订单联系客服

安装优题宝APP，拍照搜题省时又省心！

更多“It is called solar cooker, a n…”相关的问题

第1题

Although the practice of the old Roman religion disappeared many centuries ago, some tra

ces of the Roman gods are still present in our daily vocabulary. The names of the Roman sun god, Sol, and the moon goddess, Luna, are used frequently in our language The word solar describes anything pertaining to the sun, and lunar anything pertaining to the moon. For example, the sun and the planets circling it are called the solar system. The period of time in which the earth circles the sun once is a solar year. The moon takes one lunar month to circle the earth. A lunar year of twelve lunar months is eleven days shorter than a solar year. In some cases our language shows how these heavenly bodies affect us directly. A room or place for sunbathing is often called a solarium. We get our word parasol from the Italian word meaning " a guard against the sun." For many centuries it was believed that the moon affected people who were mentally ill. For this reason persons who were mentally ill were often referred to as lunatics.

1).The word lunatic originally meant___.

A、twelve lunar months

B、the home of the moon goddess

C、a person on whom the moon had a bad effect

D、a guard against the moon

2).Implied but not stated______.

A、A solar year lasts about 354 days

B、Sol was the Roman sun god

C、Our calendar is based on the movements of the moon

D、Mental illness really has nothing to do with the moon

3).In comparison with the solar year, the lunar year is__.

A、twice as long

B、the same length

C、shorter

D、a few days longer

4).A parasol is used to __.

A、measure solar time

B、protect us from the sun rays

C、protect us from the gods

D、view the sun during the day

5).The best title for this selection is:___.

A、The Gods of Rome

B、The Rhythm of the Universe

C、Ancient Beliefs

D、Gods in Our Words

点击查看答案

第2题

Sunlight is free, but that is no reason to waste it. Yet even the best silicon solar cells

—by far the most【C1】______sort—convert only a quarter of the light that falls on them. Silicon has the【C2】______of being cheap: manufacturing improvements have brought its price to a point where it is snapping at the heels of fossil fuels.【C3】______many scientists would like to replace it【C4】______something fundamentally better. John Rogers, of the University of Illinois, Urbana-Champaign, is one. The cells he has【C5】______can convert 42.5% of sunlight.【C6】______improved, Dr Rogers reckons, their efficiency could rise to 50%. Their【C7】______is that they are actually not one cell, but four, stacked one on top of another. Solar cells are made of semiconductors, and every type of semiconductor has a【C8】______called a band gap that is different from that of other semiconductors. The band gap【C9】______the longest wavelength of light a semiconductor can absorb (it is transparent to longer wavelengths). It also fixes the【C10】______amount of energy that can be【C11】______from shorter wavelength. The result is that long-wavelength photons are lost and short-wave ones incompletely utilised. Dr Rogers【C12】______this by using a different material for each layer of the stack. He chooses his materials【C13】______the bottom of the band gap of the top layer matches the top of the band gap of the one underneath, and so on【C14】______the stack. Each layer thus【C15】______off part of the spectrum, converts it efficiently into electrical energy and passes the rest on. The problem is that the materials needed to make these semiconductors are【C16】______But Dr Rogers has found a way to overcome this.【C17】______solar-cell modules are completely covered by semiconductor, but in his only 0.1% of the surface is so covered. The semiconducting stacks, each half a millimeter square, are【C18】______over that surface many dots. Each stack then has a pair of cheap glass lenses【C19】______over it. These focus the suns light onto the stack, meaning that all【C20】______light meets a semiconductor.

【C1】

A．conventional

B．common

C．peculiar

D．humble

点击查看答案

第3题

Scientists continue to work on the technology to ________ solar energy more efficient

A.release

B.produce

C.protect

D.store