🔍 Key Concepts

• Reverse osmosis desalinator output is limited by how long it can be safely and reasonably operated by hand • Liferaft/survival craft required water rations are fixed by regulation, and the desalinator is allowed to supply only up to two-thirds of that amount • Think about what a realistic manual pumping period would be for survivors in an emergency

💭 Think About

• If survivors must hand‑pump enough water to cover up to two‑thirds of the required supply, how long could they realistically keep pumping without exhaustion? • Would regulations assume that people in a liferaft can operate a manual unit continuously for many days, or for a more limited time? • Compare the answer choices to what would be considered a practical operational window for a manually‑powered device in survival conditions

✅ Before You Answer

• Check what time period would be reasonable for continuous or nearly continuous manual operation under stress and fatigue • Eliminate any options that seem too short to make a real difference in water carried versus produced • Eliminate any options that seem too long to be realistically hand‑operated by weakened survivors