Answer:
a) 0.2
b) 0.2
c) 0.5
Step-by-step explanation:
Let be the event "the car stops at the signal.
In the attached figure you can see a tree describing all possible scenarios.
For the first question the red path describes stopping at the first light but not stopping at the second. We can determine the probability of this path happening by multiplying the probabilities on the branches of the tree, thus
For the second one the blue path describes the situation
For the las situation the sum of the two green path will give us the answer
