We know that Two circles in the same plane are internally tangent<span> if they intersect in exactly one point and the intersection of their interiors is not empty.
case (</span>A and B)--------> <span>are </span>externally tangent<span> case (A and C)--------> </span><span>are </span>externally tangent<span> case (B and C)</span>--------> are internally tangent
A unit rate is any quantity's value with respect to another. An example is speed expressed in kilometers per hour which is used to measure how fast a vehicle is traveling.