The lifetimes of a certain type of automobile battery are normally distributed with a mean of 5.9 years and a standard deviation of 0.4 years. The…

The lifetimes of a certain type of automobile battery are normally distributed with a mean of 5.9 years and a standard deviation of 0.4 years. The batteries are guaranteed to last at least 5 years. What proportion of the batteries fail to meet the guarantee?