【单选题】The thickness of the oil-water trasition zone is usually than the oil-gas transition zone ;the thickness of the oil-water trasition zone will be of heavier oil reservoir.( ) A.l...
【简答题】The
diagram shows a thick-walled tube. The thickness of the wall is 3mm. What is the internal diameter d of the tube?A. A. 2.8cm B. 3.1cm C. 3.4cm D. 7.4cm
【单选题】In a trunk type diesel engine piston, the thickness of the head or crown is determined by the_______Istatically balanced IIheat dissipation requirement