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Question 3 Let d, and d, be two metric space's to make up a set M 3. a) Show that D is given with D(x, y) = Max {d(x, y) , dz(x, y) } also is a metric space on M 3. b) Let a Mand r > 0. Let K, (a, r), K(a, r) and K(a, r) describe the balls around a in Mwith the radius r, regarding to the three metric spaces. Show that for 0 0. Let K, (a, r), K(a, r) and K(a, r) describe the balls around a in Mwith the radius r, regarding to the three metric spaces. Show that for 0