单项选择题
A series of trays with sieves that vibrate to remove cuttings from the circulating fluid in rotary drilling operations is called the（）.
A.shale shaker B.settling pit C.desilter D.desander
单项选择题 A semisubmersible with a positive GM，and TCG located starboard of the centerline，inclines to an angle of（）.
单项选择题 A semisubmersible with a negative GM flops to an angle of（）.
单项选择题 A semisubmersible which flops between forward and aft angles of trim is likely to have（）.
