Final answer:
The Challenger 650's Minimum Operating Empty Weight (MOEW) is essential for aviation operations, but the provided information doesn't include the exact MOEW figure, thus an accurate answer cannot be deduced from the options without the correct reference.
Step-by-step explanation:
Regarding the Challenger 650 aircraft, its operational details like empty weight are essential for various calculations in the aviation industry, not limited to fuel planning, payload capacity, and flight planning. For a particular aircraft like the Challenger 650, the manufacturer provides specific weights including the Minimum Operating Empty Weight (MOEW), which is a crucial figure for operators. Although the student question is geared toward finding a specific weight from given options, the information provided relates to weight conversions and energy density metrics, which do not directly provide the answer to the aircraft's MOEW. Therefore, without accurate reference to the Challenger 650's manufacturer specifications, choosing from the given answer options (a through d) would be a guess and is not advisable.