此题为多项选择题。请帮忙给出正确答案和分析,谢谢!
A、Both re prepred using high temperture pyrolysis
B、oth are pyrolyzed aove 2000 oth are pyrolyzed aove 2000℃
C、Both are based on polyarylonitrile preursor fibers
D、Both are mainly composite of carbon