To address Ezra's goal and identify the correct metric related to it, let's analyze the options provided:
1. A heart rate that is lowered by 10 percent: This metric refers to a change in Ezra's heart rate. While monitoring heart rate can be a part of his training, it is not directly related to his specific goal of increasing his running distance. Therefore, this option is not the best match for the metric based on his goal.
2. An increased running distance of four miles: Ezra's goal is to increase his running distance. The phrase "an increased running distance of four miles" directly aligns with his objective of running a longer distance, making it the most relevant metric.
3. The current running distance of two miles: Although knowing Ezra's current running distance is important, this metric describes his starting point, not the progress towards his goal. Hence, it is not the metric based on his goal.
4. The use of a running app or fitness tracker: While using a running app or fitness tracker can assist Ezra in monitoring his progress, it is more of a tool rather than a direct metric reflecting his goal accomplishment.
Given the analysis of each option, the metric that directly reflects Ezra's goal is:
An increased running distance of four miles
Thus, the correct choice is:
2
