A.茶褐色表底質(zhì)為泥質(zhì) B.黑色表底質(zhì)為泥質(zhì) C.灰色表底質(zhì)為沙質(zhì) D.茶褐色表泥質(zhì)有機(jī)底
A.紅 B.綠 C.褐色 D.清澈
A.5ppt B.10ppt C.14ppt D.28ppt