The model will be 5 times longer that stated.
E.g if the model is said to be 10 feet long using this scale.
10*5=50
50 feet
Its a ray. The definition of a ray is "A line which starts at a point with given coordinates, and goes off in a particular direction to infinity" A is the point and the arrow shows that it goes until infinity.
has two points of discontinuity at
, where
.
We have

so as long as
, we can cancel
and be left with
. Then as
, we have

The limit exists, so the discontinuity at -1 is removable (so definitely not C or D).
Meanwhile,

does not exist, so the discontinuity at 1 is non-removable, making A the correct answer.