Encyclopedia knowledge volume and answers

1 Why do you see lightning first and then hear thunder? Light waves travel faster in air than sound speed.

Who was the first Olympic champion in China? (Xu Haifeng)

Who invented glasses? (Luigi, bacon)

Why does the bicycle move? (Bicycle tires rub against the ground)

Whose title is the following? (Poet Fairy-Li Bai, Poet Sage-Du Fu, Shi Gui-Li He Landscape Poet-Meng Haoran, Pastoral Poet-Tao Yuanming)

What does the light of June revolve around? How long is a cycle? (Earth) (24 hours)

What are the three plains in China? (Northeast Plain, North China Plain, Middle and Lower Yangtze Plain)

How many earthquakes occur on the earth every year? (about 5 million times)

What is the smallest and coldest star? (Pluto)

10 What is the thickness of the earth? (atmosphere)