At high temperature and low pressure. B. At low temperature and high pressure. C. At low temperature and low pressure. D. At high temperature and pressure.
A. Water-tube boiler. B. Fire-tube boiler. C. Exhaust boiler. D. Composite boiler.
A. Boilers. B. Water-tube boiler. C. Fire-tube boiler. D. Steam.
A. Fire-tube boiler. B. Water-tube boiler. C. Exhaust boiler. D. Scotch boiler
A welding machine. B. A drilling machine. C. A grinding machine. D. A cutting machine.