Find the required probabilities using the exponential density function f(t) = 1 e−t/, [0, ∞). The time t (in years) until failure of a component in a machine is exponentially distributed with = 4.5. Find the probabilities that the lifetime of a given component will be less than 1 year, more than 3 years but less than 6 years, and at least 7 years. (Round your answers to three decimal places.)