We use the Pythagorean Theorem: c^2=a^2+b^2. In this case :
c-nearest range between two radios
a=22 m ( height of a building)
b=50 m ( distance from an entrance)
c^2=22^2+50^2˝=484+2500=2984
Finally: c=sqrt(2984) (square root of 2984)=54.626 m
Answer: The range of communication for the two radios is 54.626 meters.