【单选题】A large valve,usually installed above the ram preventers,that forms a seal in the annular space between the pipe and wellbore or,if no pipe is present,on the wellbore itself is called the().
A.
annular blowout preventer
【多选题】In a ( ) reservoir, fluid flows radially from the reservoir to the wellbore.
【判断题】社会主义思想认识的第一次历史性飞跃是社会主义从空想到科学的发展,它是在19世纪40-90年代实现的。( )
【判断题】科学社会主义从理论到实践,从苏联一国实践到十几个社会主义国家的实践,丰富了人们对社会主义的认识,这就是社会主义思想认识中的第二次历史性飞跃。( )
【单选题】Which of the following situations indicates that the wellbore has been damaged? ( )