连接同名磨牙颊舌尖所成的曲线为()
A.
B.平面
C.横曲线(Wilson曲线)
D.纵曲线(补偿曲线)
E.司比曲线(Spee曲线)
参考答案:C
Was it from the lake________he often went fishing________he saved the drowning girl? [ ]
A. that; that
B. where; where
C. where; that
D. that; where
若硫磺回收装置酸性气来量共19875立方米,浓度为91%,实收硫磺23268.4千克,求按硫潜含量计的硫磺收率。(结果保留两位小数)