Mobile phones? /have/got/your/cousins и дать ответ

Have your cousins got mobile phones? Yes, they have 

1. Has this letter been signed?
2. Medical students are taught the Latin language.
3. The economic agreement has been already concluded.
4. The goods haven`t been delivered yet.
5. The letter has been written and printed.
6. This problem has been solved by the Russian scientists.
7. What is sold in this store?
8. This building has been fully renovated.
9. Boxes have been counted, they can be driven to the warehouse.
10. I am not often told about it.
11. What is produced in this factory?
12. These books are sold in all bookstores in Moscow.
13. Books and textbooks are printed in 119 languages.
14. All economic books have been read by the students.
15. Have all the rules been memorized and understood?

What must the public transport of the future be?
What time is coming?
What are the two main problems?
What are any modern vehicles which may become a usual means of transport in the future?
How can we use the small electric car?
What will be possible for us to se­lect with an automatic guid­ance system for cars?
What for can we use an automatic guidance system?
What will a driver select arriving at the motorway?
What part is sophisticated electronics playing in current automotive research?
What does General Motors Corporation make in every gasoline-powered car?
What are Ford cars equipped with?
What may a radar do? 
How does the radar aerial look like?
What  car of a new generation is a Japanese company designing? What are its characteristics?
 What engine has been developed in Japan?
What are many im­portant parts made of?
What doesn`t the engine need?