Then the volume of the air part at this time is
400- 15 * sec (1)
According to the meaning in the question, the rest is 5 cm when it is inverted.
Its volume is 5*S (2)
Because (1) and (2) are equal.
That is, 400-15 * s = 5 * s.
Find s = 20 square centimeters.
The volume of the existing beverage in the bottle = 15 * 20 = 300 cubic centimeters.
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