Answer: The new pressure is 66.66 mL.
Explanation:
Given : [tex]V_{1}[/tex] = 10 mL, [tex]V_{2}[/tex] = 3 mL
[tex]P_{1}[/tex] = 20 atm, [tex]P_{2} = ?[/tex]
Formula used to calculate the new pressure is as follows.
[tex]P_{1}V_{1} = P_{2}V_{2}[/tex]
Substitute the given values into above formula as follows.
[tex]P_{1}V_{1} = P_{2}V_{2}\\20 atm \times 10 mL = P_{2} \times 3 mL\\P_{2} = \frac{20 atm \times 10 mL}{3 mL}\\= 66.66 mL[/tex]
Thus, we can conclude that the new pressure is 66.66 mL.