For a certain machine type you are given the following information: 80% of the machines fail by age 4; - 20% of the machines do not fail by age 4; For the 80% of machines that fail by age 4, the distribution of failure times is a continuous uniform random variable on (0,4). A special warranty on this machine-type provides replacements: For the machines that fail by age 4, there will be replacement at the time of failure - For the machines that do not fail by age 4, there will be replacement at age 4 (even though they have not failed). Let Y be the age of the machine at the time of replacement. Calculate Var-(Y). Possible Answers