- A282
- B287
- C572
- D286
Step-by-Step Solution
The layers form the AP 40, 37, 34, ..., 4 with and . Then , so . The value 282 stops at 7 sacks , forgetting the "+1"), 287 carries the pile down to 1 sack , and 572 omits the factor .
Answer: D) 286
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