Kelvin chooses a pair of trousers and a shirt to wear for college. He chooses grey trousers or black trousers. He chooses a red shirt or a yellow shirt. The probability that he chooses grey trousers is 1/3. The probability that he chooses a red shirt is 2/5. His choice of shirt is independent of his choice of trousers. [Figure: Partially completed tree diagram for Trousers and Shirt choices]

1. (a)Complete the tree diagram.[2]
2. (b)What is the probability that Kelvin chooses grey trousers and a red shirt?[1]
3. (c)What is the probability that Kelvin does not choose either black trousers or a red shirt?[2]

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