3 Precision-Recall Curves [20pts] A Precision-Recall (PR) curve expresses precision as a function of recall. Usually, a PR-curve is computed for each query in the evaluation set and then averaged. For simplicity, the goal in this question is to draw a PR-curve for a single query. Draw the PR-curve associated with the ranking in Exercise 2 (same query, same results). (Hint: Your PR curve should always go down with increasing levels of recall.) 3 Precision-Recall Curves [20pts] A Precision-Recall (PR) curve expresses precision as a function of recall. Usually, a PR-curve is computed for each query in the evaluation set and then averaged. For simplicity, the goal in this question is to draw a PR-curve for a single query. Draw the PR-curve associated with the ranking in Exercise 2 (same query, same results). (Hint: Your PR curve should always go down with increasing levels of recall.)