Can you explain me how to do integration in physics in a easy way?

The easiest way to explain it is roughly identical to the way that your teacher explained it in class.  If there were any easier way ... like writing it here in a few paragraphs ... then that's what the teacher would have done.  You would have been given the easy explanation on the first day of class, printed on one sheet of paper, and you would have had the rest of the year to practice it and get really good at it.
If the class spent a month teaching it, then that's about how long it takes.  Sorry.

answer and explanation;

composition refers to both the types of minerals within a rock and the overall chemical makeup of the rock while texture refers to the size and arrangement of the minerals or grains that make up a rock. both composition and texture can be used to classify rocks, such as igneous rocks. texture describes how the rock became solid or crystallized from liquid, melted rock. composition of a rock describes the minerals that make up a particular rock.