问题详情

What does Werner J, A. Dahm say about the Hyper-X test flight？
A．It was unsuccessful because it lasted only 11 seconds.
B．It is a very important event in developing very fast airplanes.
C．It allows people to fly at an altitude of 100,000 feet.
D．It can transport cargo quickly and cheaply to outer space.请帮忙给出正确答案和分析，谢谢！