The time between emissions of beta particles by radioactive source is random and exponentially distributed with a mean time E[T] between emissions of five seconds and a probability density function of the form fr (t) = Ke EThu(t) 1. What is the value of K ? 2. If an emission has just occurred what is the expected time until the next emission occurs? 3. If A = {T > 1}, find the value of E[T|A], the expected time between emissions given that we know it is greater than one second.