X is the lifetime of computer modeled as a Rayleigh variable with an average lifetime of 5 years and Y represents the lifetime of another computer modeled in terms of a Rayleigh variable with an average lifetime of 6 years. The lifetimes are independent. 1. What is the probability that both of them last beyond their average lifetimes? 2. What is the probability that only one lasts beyond its average lifetime? 3. What is the probability that at least one lasts beyond its average lifetime?