Notice that volume of water doesn't change when you turn the bottle upside down.

Since volume that is empty = total volume - volume of water inside,

The volume of empty space inside must the same for both orientations of the bottle.


Volume of empty space in Figure 2

= 2.3cm x 10.4cm²
= 23.92cm³

This equals the volume of empty space in Figure 1

Volume of water in Figure 1

= 4.6cm x 10.4cm²
= 47.84cm³

Total volume or capacity
= Volume of water + volume of space
= 47.84cm³ + 23.92cm³

= 71.76cm³

Thank you for your help

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