There is a circular park of radius 5 meters. Three friends Farida, Somaiya and Farid are sitting at equal distance on its boundary each having a toy telephone (connected using strings) in their hands to talk each other. Find the length of the string between a pair of the telephones.
In 2008, the meteorological office predicted the weathers completely right for the months of february and april, and completely wrong for all the other months. What is the probability that the forecast was wrong for a given day that year?