Name two common small engines used on farms and describe one maintenance task for each.

• A. Diesel-powered pump engine — maintenance: replace spark plug; Gasoline-powered four-stroke engine (e.g., lawn mower) — maintenance: change oil filters
• B. Gasoline-powered four-stroke engine (e.g., lawn mower) — maintenance: clean/replace air filter and spark plug; Diesel-powered pump engine — maintenance: change oil and replace fuel filter
• C. Electric motor — maintenance: replace batteries; Steam engine — maintenance: clean boiler
• D. Hydrogen-fueled engine — maintenance: refuel; Nuclear-powered engine — maintenance: shield cooling

Answer: (B)