During the course of a day, the vehicle traffic at a certain location varies randomly, changing among light, medium, and heavy. imagine a three-state continuous time markov process where changes in traffic density are represented by transitions. assume the only way to get from light to heavy or vice versa is by way of medium. the transition times are exponentially distributed. assume the parameter values are λlm = 4, λml = 3, λmh = 2, λhm = 1 in units of transitions per hour. find the percentages of time that the traffic is light, medium, and heavy.