How should a damaged fuel tank be temporarily secured?

A damaged fuel tank should be temporarily secured by applying a suitable patch. This method is effective because it helps to seal the breach in the tank and prevents further leakage of fuel, which is critical for safety in emergency situations. Using a proper patch allows for containment of the fuel, thereby reducing the risk of fire and environmental contamination until a permanent repair can be carried out.

The other options, while they may seem plausible in some contexts, do not provide an effective or safe solution for securing a damaged fuel tank. Filling the tank with sand could lead to blockage or ineffective sealing, while submerging it in water is impractical and could introduce other complications. Leaving the tank open for ventilation does not address the issue of fuel leakage and could expose it to additional risks. Therefore, applying a suitable patch is the most viable and safest approach to temporarily secure a damaged fuel tank.