有关纬线和纬度的说法正确的是[ ]
A、所有纬线长度相等
B、纬线指示东西方向
C、两条相对的纬线构成一个纬线圈
D、北极点的纬度为0°
答案：B
When he was in the office, he preferred ____ something ____ nothing.
A．to do; than do
B．to do; rather than
C．doing; rather than doing
D．doing; to doing
为什么管箱要作焊后热处理？
