问题详情

What did Werner J．A．Dahm of the University 0f Michigan say about the Hyper X test night？
A．It indicated the birth of a very fast airplane．
B．It was self-powered，so it lasted only 1 l seconds．
C．It can transport cargo quickly and cheaply to the brink of space
D．It is a major milestone in the journey of making a new type of Very fast airplanes 请帮忙给出正确答案和分析，谢谢！