Consider a graph whose vertices are points in the plane with integer…

Consider a graph whose vertices are points in the plane with integer co-ordinates $(x,y)$ such that $1\leq x\leq n$ and $1\leq y\leq n$, where $n\geq 2$ is an integer. Two vertices $(x_1,y_1)$ and $(x_2,y_2)$ are adjacent iff $|x_1-x_2|\leq 1$ and $|y_1-y_2|\leq 1$. The weight of an edge $\{(x_1,y_1),(x_2,y_2)\}$ is $\sqrt{(x_1-x_2)^2+(y_1-y_2)^2}$.

(a) What is the weight of a minimum weight-spanning tree in this graph? Write only the answer without any explanations.

(b) What is the weight of a maximum weight-spanning tree in this graph? Write only the answer without any explanations.