Ответьте пжл на вопросы по тексту ( вопросы указаны после текста)Transportation

Ответьте пжл на вопросы по тексту ( вопросы указаны после текста)
Transportation used to be much slower than it is now.
For many years in desert, camels used to be the only form of transportation. Before the age of modern trains, camel trains used to carry all the goods for trading between Central Africa and Europe. Traders sometimes used to put together camel trains with 10,000 to 15,000 animals. Each animal often carried as much as 400 pounds and it could travel twenty miles a day. This form of transportation used to be so important that camels were called the "ships of the desert".
Now modern trains travel across the desert in a very short time. One engine can pull as much weight as 135,000 camels. In addition, trains use special cars for their load. Refrigerator cars carry food; boxcars carry heavy goods; and tank cars carry oil.
Air travels has changed too. The earliest planes were biplanes, with two sets of wings. The top speed of this plane was 60 miles per hour. The pilots used to sit or lie on the wings in the open air. The plane engines sometimes used to stop in the middle of a trip. It was impossible to fly in bad weather. In snow or rain, the wings frequently became icy. Then the plane might go down.
Mechanical improvements during the First World War changed airplanes. Monoplanes took the place of biplanes. Pilots flew inside of covered cabins. Still, even these planes were small. Only rich people were able to travel in airplanes.
Now modern jets make air travels possible for all people. Further improvements have lowered the cost of flying, and they have made air travel much safer than it used to be. A modern 707 can carry 170 people and can fly at 600 miles per hour. People never used to eat, sleep, or watch movies on airplanes. Now these things are a normal part of air travel.

Ответьте на вопросы по тексту:
1.What used to be the only form of transportation in the desert?
2.What did people use to call the camels?
3.Why air travels were so dangerous?
4.Did pilots use to travel in bad weather?
5.Are air travels safe and comfortable now?