1 is the answer.
The exact answer is 1.03, but we have to round it to the nearest tenth which is 0 because 3 is less than 5.


keep in mind, that "t" is the time when the train at A station, left towards B station
they met, at some time "t", and by the time that happened, train from A
which started 3 hours earlier, had already covered "d" distance,
whatever that is
and the train coming from B, covered, 600-d, or the difference
First add 5 to right side

Next , to cancel the 7, you need to multiply by 7 on both sides
Answer:
Always linear...
Decreases with successive trophic level