A. Annex B B. Annex C C. Annex D D. Annex E Answer: C Analysis: The gas production standard corresponds to ISO 1217 Annex D.

A. Screw B. Piston C. Centrifugal wheel D. Scroll disk answer: B. piston

A. Noise is loud B. Low efficiency C. Maintaining complex D. Low noise and high efficiency Answer: D. Low noise and high efficiency

A. Small flow B. Low power C. Not suitable for occasions with small gas volume and too high pressure ratio D. Complex structure answer: C. Not suitable for occasions with small gas volume and too high pressure ratio

A. A few hundred yuan to several thousand yuan B. Thousands of yuan to tens of thousands of yuan C. Tens of thousands to hundreds of thousands of yuan D. Hundreds of thousands of yuan to several million yuan Answer: B. Thousands to tens of thousands of yuan

A. Produce lubricating oil B. No lubricating oil C. Need to replace lubricating oil frequently D. High noise answer: B. No production of lubricating oil

A. 1873 B. 1871 C. 1965 D. Answer in 2017: A. in 1873

A. Small market share B. Few product types C. Insufficient technological innovation D. Large market share and rich product categories Answer: D. Large market share and rich product variety

A. Poor after-sales service B. The after-sales service network is underdeveloped C. Provide comprehensive after-sales service D. After-sales service is limited to large cities Answer: C. Provide comprehensive after-sales service

A. Backwardness of energy-saving technology B. Advanced energy-saving technology C. Don’t pay attention to energy-saving technologies D. General answer to energy-saving technology: B. Advanced energy-saving technology