A little airplane has given new meaning to the term going hyper. The Hyper-X is an unmanned,experimental aircraft just 12 feet long. It achieves hypersonic speed using a special sort of engine known as a scramjet3.It may sound like something from a comic book,but engineers have been experimenting with scramjets since the 1960s. Out of the three experimental Hyper-X aircrafts built for NASA5,only one is now left.The agency has plans for another 11-second hypersonic flight,this time at 10 times the speed of the sound. 1. The Hyper-X broke the record because B it flew along the equator. D it traveled at a supersonic speed.
2017届高考英语一轮复习课时作业:unit 23 Conflict(北师大版)
2017届高考英语一轮复习限时训练:3-5 Canada“The True North”(新人教版)
2017届高考英语一轮复习课时作业:unit 15 Learning(北师大版)
2017届高考英语一轮复习课时作业:unit 2 Heroes(北师大版)
2017届高考英语一轮复习限时训练:2-5 First aid(新人教版)
2017届高考英语一轮复习课时作业:unit 8 Adventure(北师大版)
2017届高考英语一轮复习限时训练:1-4 Earthquakes(新人教版)
2017届高考英语一轮复习课时作业:unit 1 Lifestyles(北师大版)
2017届高考英语一轮复习限时训练:2-3 Computers(新人教版)
2017届高考英语一轮复习课时作业:unit 7 The sea(北师大版)
2017届高考英语一轮复习课时作业:unit 4 Cyberspace(北师大版)
2017届高考英语一轮复习课时作业:unit 10 Money(北师大版)
2017届高考英语一轮复习限时训练:3-2 Healthy eating(新人教版)
2017届高考英语一轮复习学案:必修2 unit 5 Rhythm(北师大版)
2017届高考英语一轮复习限时训练:2-2 The Olympic Games(新人教版)
2017届高考英语一轮复习学案:必修2 unit 6 Design(北师大版)
2017届高考英语一轮复习课时作业:unit 24 Society(北师大版)
2017届高考英语一轮复习课时作业:unit 19 Language(北师大版)
2017届高考英语一轮复习限时训练:1-5 Nelson Mandela-a modern hero(新人教版)
2017届高考英语一轮复习限时训练:2-1 Cultural relics(新人教版)
2017届高考英语一轮复习课时作业:unit 17 Laughter(北师大版)
2017届高考英语一轮复习限时训练:4-3 A taste of English humour(新人教版)
2017届高考英语一轮复习课时作业:unit 13 People(北师大版)
2017届高考英语一轮复习限时训练:4-5 Theme parks(新人教版)
2017届高考英语一轮复习课时作业:unit 18 Beauty(北师大版)
2017届高考英语一轮复习限时训练:4-2 Working the land(新人教版)
2017届高考英语一轮复习课时作业:unit 21 Human Biology(北师大版)
2017届高考英语一轮复习课时作业:unit 16 Stories(北师大版)
2017届高考英语一轮复习限时训练:3-1 Festivals around the world(新人教版)
2017届高考英语一轮复习课时作业:unit 6 Design(北师大版)
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