1 ptsD,D1Official number: 6924
Can you add water to the cooling system of a bus engine?

Explanation
Correct answer: Yes, but only in emergency situations and when ambient temperature is above zero.
The engine cooling system should be filled with a specialised fluid, which has a significantly lower freezing point than water. Adding water is permissible only in emergency situations as, in sub-zero temperatures, it could freeze and rupture the system's components, leading to serious engine damage.