题干

下列有关太阳的说法,正确的是(  )

A:太阳巨大的能量来自其本身的核裂变

B:煤炭、石油等矿产是地质历史时期岩石固定以后积累下来的太阳能

C:太阳活动指的是太阳在银河系中的周期性转动现象

D:太阳辐射是促进地球上的水、大气运动和生物活动的主要动力

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答案(点此获取答案解析)

D

同类题3

Psychology(心理学)tells us that many people hate to take risks. But it is good for us to take risks, especially when the risk is to achieve a desired(渴望的) result. In that way, we become stronger and braver.
Our human nature should be to take risks, but some people just sit and wish they didn’t have the fear to move on. This is because they failed a few times in their lives. Please step out and don’t let the past hold you back from living life to the fullest. Move forward and move on! In studying the psychology of taking risks, we find that human nature provides us with the desire to experiment and take chances.
Risk taking is a great advantage that allowed our ancestors(祖先) to become stronger and stronger day by day. By taking risks they fought off enemies and discovered new territories(领土). This attitude has become a part of our modern culture. Riding a roller coaster is a common risk taking activity. Even each person seems to enjoy the risk although they have the understanding that it is dangerous. This psychological and biological (生物学的) connection creates an interesting connection between what is unsafe and what humans enjoy.
Getting in a car each day is a risk. Getting out of bed is a risk, too. We need to take risks so that we can complete many things. Astronauts take risks when they get inside a rocket(火箭); however, the things they achieve are great. Businessmen take a risk when they buy parts of a company. However, without doing that, they could not make more money.
We need to take risks so that we can gain(获得) something. It is impossible to move forward in life, earn money, enjoy a relationship, play a sport, or do anything else without taking a risk. It is all part of the game. It’s one of the most important parts of life.