They could have travelled any distance. In total, they travelled 1.75 times the distance of the first day, but since we do not know the distance of the first day, we have no idea the actual distance. For all we know they could have gone to the moon in the first day.
Answer:
Slope: 1
Y-intercept: (0,3)
Step-by-step explanation:
The y intercept is when the slope reaches the y-axis line. In this case, it is given to us. Anything that is formed like this: (0, y) is the y-intercept.
Y intercept: (0, 3)
For slope, you can use the formula rise over run. 
From the picture, I have drawn the rise over run, which is
, which is also 1.
Slope: 1
Hope this helped.
Here I have attached a photo to help you with this:
Answer:
the answer is 2/1 or just 2