Fuel consumption after driving for 2 hours: 25x(80x2)/ 100, remaining fuel consumption:100-25x (80x2)/100 = 60;

Fuel quantity: 250-60= 190 (liter)

2. Find the analytical function of the remaining fuel quantity Y in the fuel tank and the driving time X before refueling.

y = 100-25 * 80x/ 100 = 100-20x，0 & lt= x & lt=2;

3 If the remaining fuel in the fuel tank is 10L, the fuel gauge will give an alarm, prompting that it is necessary to refuel, and the bus will no longer run continuously. How far can the bus run? At this point, how long has the bus been running since it started?

Analytical function between the remaining fuel quantity y of fuel tank and the driving time x after refueling.

y=250-20(x-2)=290-20x，2 & lt= x；

y= 10，

10=290-20x，x=280/20= 14(h)

Ran x-2= 14-2= 12(h)

Then the farthest distance that a car can run (after refueling) is 80x12 = 960 (km);

At this point, the bus started running:14h;