Blank / blank equals 1 2/7

The answers are: 
a.)102.02
a.)242.47 

The volume of the cone can be expressed as:

where:
V - the volume of the cone,
r - the radius of the cone,
h - the height of the cone.

It is given:
h = 12 in
R = 2r = 5.7 in     ⇒     r = 5.7 in ÷ 2 = 2.85 in
π = 3.14

Therefore, the volume of the original conical chamber (V₁)


Further, the new chamber is scaled by a factor of 1.5. That means that radius and height of the original chamber are increased 1.5 times:
r₁ = r · 1.5 = 2.85 in · 1.5 = 4.275 in
h₁ = h · 1.5 = 12 in · 1.5 = 18 in

The volume of the new chamber is:


The difference between two chambers is:
V₁ - V = 344.49 - 102.02 = 242.47