21) What type of abrasives is used for grinding of tough materials?

22) What type of abrasives is used for grinding of very hard materials with low tensile strength?

23) Which main part of the surface grinding machine has a driving mechanism?

24) Which part of the surface grinding machine reciprocates along the guideways to provide longitudinal feed to the work?

25) Which part of the surface grinding machine mounted on the column and it can be moved vertically up and down?