Necessary AssumptionDiff: Medium
Logic Breakdown
Passage Summary: We couldn't go to Mars because the fuel for the trip back made the ship too heavy to take off. Now that we have a machine that makes fuel once we get there, the weight problem is solved.
Conclusion: It is now feasible for humans to travel to Mars and return using a spacecraft equipped with the new fuel-manufacturing device.
Reasoning: Weight was the only physical obstacle to a Mars mission because carrying return fuel made ships too heavy to launch; however, a new device can now create that return fuel on Mars.
Analysis: The argument relies on the 'Gap' that solving the weight of the return fuel is the final piece of the puzzle. It assumes that the fuel-manufacturing device itself doesn't weigh so much that it cancels out the weight savings it provides. Furthermore, it assumes that the Martian atmosphere actually contains the specific raw materials required for the device to function. Look for an answer that confirms the device is practical to carry and that the necessary resources on Mars are actually available.
Conclusion: It is now feasible for humans to travel to Mars and return using a spacecraft equipped with the new fuel-manufacturing device.
Reasoning: Weight was the only physical obstacle to a Mars mission because carrying return fuel made ships too heavy to launch; however, a new device can now create that return fuel on Mars.
Analysis: The argument relies on the 'Gap' that solving the weight of the return fuel is the final piece of the puzzle. It assumes that the fuel-manufacturing device itself doesn't weigh so much that it cancels out the weight savings it provides. Furthermore, it assumes that the Martian atmosphere actually contains the specific raw materials required for the device to function. Look for an answer that confirms the device is practical to carry and that the necessary resources on Mars are actually available.
Passage Stimulus
Passage Redacted
Unlock Full Passage9.Which one of the following is an assumption on which the argument depends?
Correct Answer
E
Correct. The argument depends on the device solving the weight problem. Negation test: if the device does not weigh less than the return-trip fuel that would have been launched, then the craft would still be too heavy at launch and the conclusion that a crewed round trip is possible no longer follows. So E is necessary.
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