Answer:
The fourth one is correct ( D/ number 4).
d is right hope this helps:)
H3PO4 is the formula for hydrophosphoric acid
18 L
Explanation:
boyles law
P1V1 = P2V2
V2 = P1V1/P2
V2 = (.9 * 4)/.2
V2 = 18
Sorry its tooo blurry