Answer: 364.5 cm3 OR if you are talking with volume: 4.5 cm3
For Centimeter
From the Boyle's law, we know that pressure is inversely proportional to volume. Hence, the volume of the oxygen gas will become 364.5cm³.
For Volume
Given that the pressure on 9 cm³ of oxygen gas is doubled, we can say:
Initial pressure (P₁) = P
Final pressure (P₂) = 2P (double the initial pressure)
According to Boyle's Law:
P₁V₁ = P₂V₂
P x 9 = 2P x V₂
9 = 2V₂
V₂ = 9 / 2
V₂ = 4.5 cm³
Therefore, when the pressure on 9 cm³ of oxygen gas is doubled at a fixed temperature, its volume will become 4.5 cm³.
Please, brainliest, and hoped this had helped you.