4.4. Quadrilateral $K L M N$ with sides $M N=6, K L=2, L M=5$ is inscribed in a circle. Determine the distance between the midpoint of side $K N$ and the line $L M$, if the lines $K M$ and $L N$ are perpendicular. Round the answer to two decimal places if necessary.
Answer: 3.44 (exact value: $\frac{\sqrt{15}+3}{2}$ ).