Which of these is the coarsest grit abrasive that may be used on aluminum?

36 grit

80 grit

RS

120 grit

180 grit

80grit

Explanation:

80 grit is coarsest grit that may be used on aluminum

The lowest grit sizes range from 40 to 60. From the given options 80 grit is practically available grit.

What is a sandpaper used for?

They are essentially used for surface preparation. Sandpaper is produced in a range of grit sizes and is used to remove material from surfaces, either to make them smoother (for example, in painting and wood finishing), to remove a layer of material (such as old paint), or sometimes to make the surface rougher (for example, as a preparation for gluing).