Can anybody answer this question #13 and tell me how they got the answer.... thank you

Answer:
C 6
Step-by-step explanation:
The point P is the centroid of the triangle (the intersection of medians). The centroid divides the median into parts in the ratio 2:1, with the longer part between the centroid and the vertex.
Here, that means ...
NP/PQ = 2/1
NP = 2·PQ = 2·3
NP = 6