Final answer:
The Lundberg upper bound for the probability of ultimate ruin in a continuous-time surplus model can be calculated using the formula: Lundberg upper bound = (initial surplus) / (premium loading factor).
Step-by-step explanation:
In a continuous-time surplus model, the Lundberg upper bound for the probability of ultimate ruin can be calculated using the formula:
Lundberg upper bound = (initial surplus) / (premium loading factor)
In this case, the initial surplus is 2 and the premium loading factor is 0.25. Therefore, the Lundberg upper bound for the probability of ultimate ruin is:
Lundberg upper bound = 2 / 0.25 = 8