A car has five traffic lights on its route. Independently of other traffic lights, each traffic light turns red as the car approaches the light (and thus forces the car to stop at the light) with a probability of 0.4.
a. Let K be a random variable that denotes the number of lights at which the car stops. What is the PMF of K?
b. What is the probability that the car stops at exactly two lights?
c. What is the probability that the car stops at more than two lights?
d. What is the expected value of K?