A $20mm50mm50mm$ zinc casting is produced. After cooling to room temperature, the casting is found to weigh $90$ g $.$ The density of the zinc is $7\mathrm{.}13\frac{g}{c}{m}^3.$ Determine:

me of the shrinkage cavity at the center of the casting:

$($b$)$ the percent shrinkage that must have occurred during solidification.

Round your answers to two decimal places.

$($a$)$ The volume of the shrinkage cavity is: $c{m}^3$

$($b$)$ The percent shrinkage is: $\%$