<span>0.00001581 light years (earth's distance from sun) </span>
I believe one minerals that cleaves into flat sheets are called Mica. there are others too, though.
Typically, the background of a study includes a review of the existing literature on the area of your research, leading up to your topic. Once you have discussed the contribution of other researchers in the field, you can identify gaps in understanding, that is, areas that have not been addressed in these studies.
Not sure if this is what you meant, if not, let me know
Holaaaaaaaaaaaaaaaaaaaaaaaaaaa
<span>Earth is the densest planet known. </span>
