Answer the questions.

HOW CUSTOMS WORKS
Most countries maintain a number of different border-patrol agencies that work together and separately to regulate who and what comes in and out of the country.
In apprehending and prosecuting the smugglers, the agencies would all have to work together.
The United States Customs Service uses advanced, radar-equipped airplanes to patrol the coast from above. At a few airports, customs uses room-sized X-ray machines to look through a person's clothes for any mysterious bulges. At the main border crossing between the United States and Mexico, customs agents use an X-ray machine large enough to scan entire cars and trucks. Some agents are also equipped with handheld electro vacuum devices that analyze the particles in the air around a package or piece of luggage. Using these sensitive sniffers, the agents can quickly determine if there are explosives or drugs inside.
Customs agencies also use drug-sniffing and bomb-sniffing dogs to stop smugglers. These animals go through an intense training process that teaches them to recognize and locate particular odors in exchange for some play time. In airports, customs agents let the dogs sniff out arriving passengers' luggage and sometimes the passengers themselves.
Additionally, agents may take the dogs on board the plane after the passengers have departed. If a passenger is carrying drugs on his or her body, the dogs might pick up the scent lingering on the seat. The agents then find out who was sitting there and pull the passenger aside for a full body search.

1. What does a nation's customs agency do in addition to monitoring legal imports?
2. What does the customs use room-sized X-ray machines for?
3. What are handheld electrovacuum devices used for?
4. What do customs agencies use drug-sniffing and bomb-sniffing dogs for?
5. What does the training process teach the animals to do?
6. Do customs agents let the dogs sniff out arriving passengers' luggage only?
7. Why may the agents take the dogs onboard the plane after the passengers have departed?
8. What methods of keeping out illegal items used by a nation's customs agency are described in the text?
9. Which method do you find more effective?
10. Would you prefer to work with machines or animals to keep out illegal items?