Answer: The expression is 7/2.
If I follow the angle degrees that they gave, your answers would be as follows:
I=145°
S=155° or 90°
E=78°
L=120° or 55°
Maybe this is right, sorry it took so long.
With the equation 4x, the x represents side length. Since we are given side length of 5/7, then the equation becomes
perimeter = 4 × 5/7
p= 20/7
p= 2 6/7 units
It can travel 125km with 5 liters
And 6 liters to travel 150 :)