弯制有缝管道时，其纵向焊缝应置于( )。
A．弯曲平面内表面上
B．弯曲平面外表面上
C．弯曲平面45°以内
D．弯曲平面45°以外
参考答案：D
若25x2=36，则x=（ ）．
All the students in our class are over fifteen except Li Lei . He is _____ in our class. [ ]
A. younger
B. the oldest
C. the youngest
D. very
