El ángulo entre los vectores: a=(-9,1) y b=(-8,7). A. 44,9°
B. 17,5°
C. 7,5°
D. 34,9°

I believe the answer is 7,5

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.