aaron and baron are playing a game with coins. suppose that aaron has a coin with probability of getting heads and baron has a coin with probability of getting heads. in each round, aaron and baron independently flip their coins at the same time. if no one gets heads, they play again. the game ends when either aaron or baron gets heads. the winner is the first one to get heads. the game may end in a tie if they both get heads in the same round. let denote the number of rounds aaron and baron play. what distribution is r?