I think the situation is modeled by the scenario in the attached image. Some specific values seem to be missing (like the height of door
)...
The door forms a right triangles that satisfies

We also have

so if you happen to know the height of the door, you can solve for
and
.
is fixed, so

We can solve for the angular velocity
:

At the point when
and
ft/s, we get

Answer:
2.5
Explanation:
25-22.5n= will give you 2.5
A. Genus and B. Species are also major levels of classification.