Read the passage given below and answer the question that follow:

1. Satellites are an important part of our ordinary lives e.g. the weather forecasts are sent by satellites. Some satellites have cameras that take photographs of the earth to show how clouds move. Satellites are used to connect our international calls. Computer connections of the world wide web and Internet also use satellites. Aeroplane pilots also sometimes use a satellite to help them find their exact location.

2. We use satellites to send television pictures from one part of the world to another. They are usually 35,880 kilometres above the equator. Sometimes we can see a satellite in the sky and it seems to stay at the same place. This is because it is moving at around 11,000 kms an hour, exactly the same speed that the earth rotates. Sometimes it moves away from its orbit, so there are little rockets on it which are used to put the satellite back in the right position. This usually happens every five or six days.

3. Space is not empty. Every week, more and more satellites are sent into space to orbit the Earth. A satellite usually works for about ten to twelve years. Sometimes, broken satellites are repaired by astronauts or sometimes brought back to Earth to be repaired. Often, very old or broken satellites are left in space to orbit the earth for a long time. This is very serious because some satellites crash into each other.

4. In the 1950s, both the United States and the Soviet Union decided to try rocketing objects into space that could be used as spy monitoring devices or may be as weapons. The very first satellite propelled into space by humans was the Russia made Sputnik 1, launched in 1957. Today, there are thousands of satellites circling Earth. "It is constantly 'falling' to the Earth, but it moves sideways so quickly that the Earth curves away from beneath it faster than it can fall. Thus it remains in the orbit, never hitting the ground." How are satellites powered once they are launched into space? "Most satellites use solar power to produce electricity a few use nuclear power".