To find the volume of the metal cube, we use the formula for density:
\[
\text{Density} = \frac{\text{Mass}}{\text{Volume}}
\]
Rearranging the formula to solve for volume, we have:
\[
\text{Volume} = \frac{\text{Mass}}{\text{Density}}
\]
Substituting the given values:
\[
\text{Volume} = \frac{63.53 \, \text{g}}{9.15 \, \text{g/cm}^3} = 6.9443 \, \text{cm}^3
\]
Since \(1 \, \text{cm}^3 = 1 \, \text{mL}\), the volume of the metal cube in milliliters is:
\[
6.9443 \, \text{cm}^3 = 6.9443 \, \text{mL}
\]
The new volume of water is the initial volume of water plus the volume of the metal cube:
\[
\text{New Volume} = 64.7 \, \text{mL} + 6.9443 \, \text{mL} = 71.6443 \, \text{mL}
\]
Rounding to three decimal places, the new volume of water is:
\[
71.644 \, \text{mL}
\]