China's second female astronaut, Wang Yaping, has given the country's first-ever video lecture from space. The whole lecture lasted about 40 minutes.

Speaking to students through live video, from the Tiangong-I space laboratory, Ms. Wang used spinning tops (旋转的陀螺), a ball and some water to explain physics in zero-gravity(失重), with the help of a fellow astronaut.

Ms. Wang used different experiments to demonstrate the concepts of weight and mass (重量和质量的概念) in space. Towards the end of the class, Ms. Wang made a film(薄膜) of water using a metal ring. She then turned the film of water into a water ball by pouring more water onto it.

Around 330 primary and secondary school students watched the lecture from a special classroom in Beijing, where they could also ask Ms. Wang questions through live video. From time to time, the students greeted her lecture with warm applause(掌声).

When answering a student's question, Ms. Wang described what she could see in space. "The stars we see are much brighter, but they do not twinkle(闪烁)," she said, "The sky we see isn't blue, but black. And every day, we can see the sun rise 16 times because we circle the Earth every 90 minutes."

About 60 million students and teachers around China also watched the lecture live on TV.

【小题1】What's the purpose(目的) of the space lecture?

A．To explain physics of zero-gravity in space.

B．To demonstrate the concept of weight and mass in space.

C．To tell us what can be seen in space.

D．To show that the Earth is far away from space.

【小题2】What does the underlined word "demonstrate" in the passage most probably mean in Chinese?

A．区别

B．强调

C．传授

D．演示

【小题3】Towards the end of the lecture, Wang Yaping made a film of water so as to .

A．play with it

B．use a metal ring

C．turn it into a water ball

D．pour more water onto it

【小题4】About  students and teachers watched the lecture both from a special classroom and on TV.

A．330

B．60,000,000

C．6,000,330

D．60,000,330

【小题5】Which is NOT true according to the passage?

A．Wang Yaping is China's second female astronaut.

B．Wang Yaping gave the lecture from space all by herself.

C．The lecture was warmly welcomed by the students.

D．The sky isn't blue but black when astronauts see it in space.