Answer: i really don’t know
Explanation:
It's B.
As you go up, the air thins out, meaning it is less dense. Since there are less molecules that can transfer heat, the temperature is lower.
Answer:
For undirected graph n(n-1) for directed graph 
Explanation:
The maximum number of edges for a undirected graph is given by
, where n is number of vertices
The maximum number of edges in directed graph is given by
, where n is number of vertices
The maximum number of edges is greater in undirected graph than directed graph