题干

质量为90kg的表演者,正在表演“轻功”踩鸡蛋的节目,表演者脚穿软底鞋,踩在3个放在泡沫模板内蛋尖朝下的鸡蛋上,3个鸡蛋的蛋壳不会破,对于“轻功”踩鸡蛋的下列说法中正确的是(  )

A:表演者具有轻功,站在鸡蛋上时,减小了作用在鸡蛋上的压力

B:鸡蛋对泡沫模板的压力和泡沫模板对鸡蛋的支持力是一对相互作用力

C:表演者受到的重力和鸡蛋对它的支持力是一对平衡力

D:表演者穿软底鞋,鸡蛋尖朝下放在泡沫模板内,主要是增大受力面积,减小了鸡蛋受到的压强,故蛋不会破

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答案(点此获取答案解析)

B,C,D

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    The traditional Chinese lunar calendar divides the year into 24 solar terms. ____ It lifts the curtain of spring. After that everything turns green and full of energy and people clearly see that the daytime is becoming longer and the weather is becoming warmer.

    ⒈Flying a kite.

    Spring is the best season for kite-flying. As a traditional folk activity, it has a history of more than 2, 000 years.____ It also has the effect of promoting blood circulation and speeding up metabolism(新陈代谢).

    ⒉Wearing fabric swallows.

    Wearing fabric swallows is a custom in some regions in Shaanxi. ____ The custom originated during the Tang Dynasty (618—907). The swallow is a harbinger(预兆) of spring and a symbol of prosperity and happiness.

    ⒊Making a Spring Ox.

    Skilled artists build the frame of an ox out of bamboo strips and the legs with wood. Then they paste(粘贴) some paper and paint onto it.____ It is said that if more red and yellow paper is used, then there will be a good harvest that year.

    ⒋____

    People in China began holding a special ceremony on the first day of the Start of Spring about 3, 000 years ago. They made sacrifices to Gou Mang, the God of Spring, who is in charge of agriculture. By the Qing Dynasty (1644—1911), welcoming spring had become an important folk activity.

A. Welcoming spring.

B. The image of an ox is complete.

C. At that time, there were eight solar terms.

D. The Start of Spring is the first solar term of the year.

E. Flying a kite can help build one's health and prevent diseases.

F. It is said that the egg can be set upright on the first day of the Start of Spring.

G. People like to wear a swallow made of colorful silk on their chests on Start of Spring.