Answer
$31.35cm^3$
Work Step by Step
Mass of Empty Flask = 56.12 g
Mass of Filled Flask = 87.39 g
Density of Water = $0.9976 g/cm^3$
Mass of Water = $87.39-56.12$
$=31.27g$
$Density=\frac{Mass}{Volume}$
$Volume=\frac{Mass}{Density}$
$=\frac{31.27}{0.9976}$
$\approx31.3452285485164395$
$=31.35cm^3$