(A) multi-stage compression (X)
(B) cold water spray (X)
(C) both A. and B. above ()
(D) fully insulating the cylinder (X)
(E) high stroke (X)
Answers: Isothermal compression efficiency, even when running at high speed, can be approached by using A. multi-stage compression B. cold water spray C. both A. and B. above D. fully insulating the cylinder E. high stroke both A. and B. above.