
Answer:
a) 16.75 cubic inches Â
Step-by-step explanation:
Cylindrical mold: Â
  V = πr²h
where V is volume, r is radius, and h is height. Â
Substituting the known values:
  V = π(2 in)²(4 in)
  V = 16π in³ = 50.26 in³
Spherical mold:
  V = 4πr³/3
Substituting the radius to the equation,
  V = 4Ï€(2 in)³ / 3 Â
  V = 32π/3 in³ = 33.51 in³
The difference is calculated below:
D = 50.26 in³ - 33.51 in³
D = 16.76 in³