A. higher
B. lower
C. Same as injection air compressor
D. unable to determine
Answer: A
Analysis: Oil-free air compressors are usually costly to manufacture, with large initial investment, but low long-term maintenance costs.
A. High noise B. Low noise C. High power D. Low power answer: B. low noise
A. Price and brand B. Performance, price and brand C. Market share and technological innovation D. Production date and transportation method Answer: C. Market share and technological innovation
Answer: It uses water lubrication and does not produce any oil-related emissions.
Answer: It can handle corrosive gases and provide reliable performance in harsh environments.
A. Large flow and high power are conducive to energy conservation B. Compact structure and good sealing effect C. Smooth operation and reliable operation D. These are all answers: D. all of the above are