Hey there!
Good luck on your assignment and enjoy your day!
~
Answer:
The domain is t ≥ 0
The range is D ≥ 0
Step-by-step explanation:

D(t) = 100t + d₀
t is the time measured in hours.
d₀ is the initial position of the train.
We can assume the distance they go is not negative so...
The domain is t ≥ 0
The range is D ≥ 0
You didn’t post an image of the graph..
We write it out as an equation:
-1 = -2v + 2/3
Rearrange:
-1 -2/3 = -2v
Multiply by negative to equal positive
1 2/3 = 2v
Make 1 into a fraction
3/3 + 2/3 = 2v
5/3 = 2v
10/6 = 2v
5/6 = v
The answer is: v equals 5/6