对一台正在工作的列管式换热器,已知α1=116W/(m2·K),α2=11600 W/(m2·K),要提高总传热系数K,最简单有效的途径是_______。( )

I am wondering if they are ____ or____.

_________ in a person’s speech or writing usually ranges on a continuum from casual or colloquial to formal or polite according to the type of communicative situation.

__________ is the act performed by or resulting from saying something; it is the consequence of, or the change brought about by the utterance.

在工业生产过程中,计算机能够对控制对象进行自动控制和自动调节的控制方式,如生产过程化、过程仿真、过程控制等。这属于计算机应用中的______。

All people, whether they be rich or poor, strong or weak, privileged or deprived，are interdependent, and _______ the common task of seeking to achieve mankinds full potential

Many boys enjoy _______ football, basketball or baseball

－ What does the sign over there read － “No person ________ smoke or carry a lighted cigarette, cigar or pipe in this area”

Duty is an act or a course of action that people __________you to take by social customs, law or religion.

Duty is an act or a course of action that people ______you to take by social customs, law or religion.

Project ______is an uncertain event or condition that，if it occurs，has a positive or a negative effect on at least one project objective，such as time，cost，scope，or quality．

传热实验时，在套管换热器中用饱和水蒸气冷凝来加热空气（空气走内管，蒸汽走环隙），为强化传热决定加装翅片，翅片应装在（）侧更为有效。