What are the reasons accounting for the failure of Spruce Goose（ ） A.The concept was ahead of time. B.The complexity of working with wood C.The project was finished behind schedule. D.The cost of building the enormous machine is high.

What are the reasons accounting for the failure of Spruce Goose（ ） A.The concept was ahead of time. B.The complexity of working with wood C.The project was finished behind schedule. D.The cost of building the enormous machine is high.

正确答案：BCD