Circles drawn in the same plane are tangent circles if they have exactly one intersection point. As shown, two circles are either internally or externally tangent to each other. With three or more circles, the circles are mutually tangent if each pair of circles is tangent. Answer Exercises 1–4. internally tangent externally tangent 3 1. How many different arrangements of mutually tangent circles can be made with three circles of radius 1 unil, 2 units, and 3 units? Explain. Make sketches to support your answer. There are different arrangements. The circles can be arranged with all three circles internally tangent in way(s). The circles can be arranged with one circle externally tangent to two internally tangent circles in way(s). The circles can be arranged with all three circles externally tangent in way(s). The circles can be arranged with one circle Internally tangent to two circles externally tangent in way(s). .​