
How many years is the equipment life of environmentally friendly oil-free air compressors usually?
A. 5-7 years
B. 7-10 years
C. 10-12 years
D. 12-15 years
Answer: C
Analysis: Environmentally friendly oil-free air compressors adopt a fully enclosed design and have an equipment life of 10-12 years, far exceeding traditional oil-lubricated models.