管道保温层施工技术要求水平管道的纵向接缝位置，不得布置在管道垂直中心线( )范围内。
A．30ο
B．45ο
C．75ο
D．90ο
参考答案：B
— Oh, this cartoon book is very interesting. Where did you buy ____? I want to buy _____, too.
— In the bookshop near my home. [ ]
A. one; one
B. it; it
C. it; one
D. one; it
筒式反应器醇烯比过高，会造成催化蒸馏塔塔釜温度高。
