In this section, you will hear a radio talk. The talk will be read only once. For questions 21 -30, complete the notes which sum

At 7: 20 pm on May 6th 1937, the world’s largest airship, the Hindenburg, floated majestically over Lakehurst airport, New Jersey, after an uneventful crossing from Germany. There were 97 people on board for the first Atlantic crossing of the season. Suddenly radio listeners heard the commentator screaming "Oh, my God! It’s broken into flames. It’s flashing terribly. " 32 seconds later, the airship had disintegrated and 35 people were dead. The Age of the Airship was over.
    The Hindenburg was the last in a series of airships which had been developed over 40 years in both Europe and the United States. They were designed to carry passengers and cargo over long distances. The Hindenburg could carry 50 passengers accommodated in 25 luxury cabins with all the a-menities of a first class hotel. All the cabins had hot and cold water and electric heating. There was a dining room, a bar and a lounge with a dance floor and a baby grand piano. The Hindenburg had been built to compete with the great luxury transatlantic liners. It was 245 metres long with a diameter of 41 metres. It could cruise at a speed of 125 km/h, and was able to cross the Atlantic in less than half the time of a liner. By 1937 it had carried 1000 passengers safely and had even transported circus animals and cars.
    The Hindenburg was filled with hydrogen, which is a highly flammable gas, and every safety precaution had been taken to prevent accidents. It had a smoking room which was pressurized in order to prevent gas from ever entering it. Both passengers and crew were searched for cigarette lighters and matches before entering the ship. Special materials, which were used in the construction of the airship, had been chosen to minimize the possibility of accidental sparks, which might cause an explosion.
    Nobody knows the exact cause of the Hindenburg disaster. Sabotage has been suggested, but experts at the time believed that it was caused by leaking gas which was ignited by static electricity. The most surprising thing is that 62 people managed to escape. The fatalities were highest among the crew, many of whom were working deep inside the airship. After the Hindenburg disaster, all airships were grounded and, until recently, they have never been seriously considered as a commercial proposition.