14. Which of the following types of lubricant is derived from wool grease and is safe
alternative to the more common petro-chemical based lubricants?
A. Grease B. Lanolin
C. Vegetable oil
D. water
15. What may be the reason for always keeping the surface of water stone plain
before sharpening edge-cutting tools? To...
A. prevent early breakage of the water stone
B. establish plain surface on the edge of the tool
C. establish balance on the surface area of a water stone
D. minimize unnecessary movement of water stone while sharpening​