Three girls Reshma, Salma and Mandeep are playing a game by standing on a circle of radius 5 cm drawn in the park. Reshma throws a ball to Salma, Salma to Mandeep, Mandeep to Reshma. If the distance between Salma and Reshma, and between Salma and Mandeep is 6 cm each. What is the distance between Reshma and Mandeep?