A.奧陶紀(jì) B.朱羅紀(jì) C.泥盆紀(jì) D.二疊紀(jì)
A.三葉蟲 B.鸚鵡螺 C.筆石 D.恐龍
A.30,50,85,800,3000 B.17,50,200,800,3000 C.30,50,200,800,3000 D.17,50,85,800,3000