| Platinum 3문제 expand_more |
| 4129 | Greedy Pie Eaters | USACO 2019 December Platinum | 0 | 0 | |
| 4130 | Bessie's Snow Cow | USACO 2019 December Platinum | 0 | 0 | |
 4131 | Tree Depth | USACO 2019 December Platinum | 1 | 3 | 33.33% |
| Gold 3문제 expand_more |
 4132 | Milk Pumping | USACO 2019 December Gold | 2 | 3 | 66.67% |
| 4133 | Milk Visits | USACO 2019 December Gold | 0 | 0 | |
 4134 | Moortal Cowmbat | USACO 2019 December Gold | 2 | 3 | 66.67% |
| Silver 3문제 expand_more |
| 4135 | MooBuzz | USACO 2019 December Silver | 2 | 6 | 33.33% |
| 4136 | Meetings | USACO 2019 December Silver | 0 | 0 | |
| 4137 | Milk Visits | USACO 2019 December Silver | 0 | 0 | |
| Bronze 3문제 expand_more |
 5381 | 헬소장 (Cow Gymnastics) | USACO 2019 December Bronze | 11 | 32 | 34.38% |
| 5382 | 나는 어디? 여긴 누구? (Where Am I?) | USACO 2019 December Bronze | 14 | 58 | 24.14% |
 5383 | 우유는 순서대로 (Livestock Lineup) | USACO 2019 December Bronze | 11 | 17 | 64.71% |
