28. Mildred, a commuter student studying at Western New England University, reported to her advisor that there are three traffic lights that she needs to pass while driving from home to school. She said that, based on her experience, 10% of the time all of the three traffic lights are green, 35% of the time exactly two of them are green, and 43% of the time exactly one of them is green. Assuming that Mildred’s observations are correct, what is the probability that on a random day she encounters

(a) no green traffic lights;

(b) at most one non-green (red or yellow) light;

(c) at least two non-green lights?