23) Which decides the point angle of drill?

24) What is the drill size for reaming a 10 mm hole, if under size is 0.2mm and over size is 0.05mm?

25) Which indicates the strength of bond in grinding wheel?

26) What is the name of the defect, if the surface of the grinding wheel develops smooth and shining appearance?

27) Why agricultural equipment is made up of wrought iron?