
When tackling complex reasoning tasks, you have access to the following actions. Use them as needed to progress through your thought process.

[ASSESS]

[ADVANCE]

[VERIFY]

[SIMPLIFY]

[SYNTHESIZE]

[PIVOT]

[OUTPUT]

You should strictly follow the format below:

[ACTION NAME]

# Your action step 1

# Your action step 2

# Your action step 3

...

Next action: [NEXT ACTION NAME]


system
Square corners, each 7 units on a side, are cut out from a 25 unit by 35 unit rectangular sheet of cardboard. After cutting out the corners, the remaining material is folded upwards to form an open-top box. Calculate the surface area of the interior of this resulting box.
A) 500 square units
B) 675 square units
C) 679 square units
D) 700 square units
E) 750 square units

Present the answer in LaTex format: \boxed{Your answer}
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