Man has invented four kinds of satellites. The first kind of satellite studies the 1 of the earth . They are used to make maps . They also help countries to see where they may 2 oil or gold .
The second kind of satellite is used to guide ships and planes. A ship or a plane can 3 a message to the satellite , and satellite can find out 4 the ship or the plane is .
The third kind studies the weather. These satellites 5 clouds and strong winds moving across the earth . They warn countries to make preparations when very 6 weather is coming . 7 kind is used for communication. Telephone calls 8 countries can be sent by these satellites . Some can carry hundreds of calls at the same time . The call is sent to the satellite , then the 9 sends it to a station in the country and this country is being phoned . These satellites also carry pictures; they can receive and send about eight 10 at a time .