Please I need urgent help. It will be a great help

Note: I need explanation and mathematical solve. not code

Apply K-Nearest Neighbor (K-NN) algorithm to determine the health status of 'subject 5'. Use the cosine similarity function to determine the nearest neighbors and consider the value of K=3. BMI Body-fat 24 45 Subject 1 Subject 2 Subject 3 Subject 4 Sunbect 5 Health Status 23 Healthy 34 Unhealthy 22 Unhealty 25 Healthy 24 ?? 27 15 28