Answer is the dot is a comma btw

Ihave trouble finding the nth term of a linear sequence

Aball is dropped from a height of 10m above the ground. it bounce to 90% of its previous height on each bounce. what is the approximate height that the ball bounce to the fourth bounce?

In the diagram, points d and e are marked by drawing arcs of equal size centered at b such that the arcs intersect ba and bc. then, intersecting arcs of equal size are drawn centered at points d and e. point p is located at the intersection of these arcs. based on this construction, m , and m