### Exercise condition:

4
Analyse the below picture and fill in the following blanks:

1. Vertex $$Q$$ is opposite to the side .
2. Side $$PR$$ is opposite to the vertex .
3. Median $$RU$$ is a line segment that connects the vertex $$R$$ to the midpoint of the opposite side .
4. By the definition of median, it can be concluded that the side $$PR$$ is twice as that of .