Two ants crawl along the perimeter of a polygonal table, so that the distance between them is always $10$ cm. Each side of the table is more than $1$ meter long. At the initial moment both ants are on the same side of the table. (a) (2 points) Suppose that the table is a convex polygon. Is it always true that both ants can visit each point on the perimeter? (b) (4 points) Is it always true (this time without assumption of convexity) that each point on the perimeter can be visited by at least one ant?