If I were to take the square root of that, which is equal to 2.5, we can now describe the normal distribution of the round trip and use that to answer the question. So we have this normal distribution that might look something like this. We know its mean is 20 liters. So this is 20 liters. And we wanna know what is the probability that Shinji runs out of fuel? Well, to run out of fuel, he would need to require more than 25 liters of fuel. So if 25 liters of fuel is right over here, so this is 25 liters of fuel, the scenario where Shinji runs out of fuel is right over here.