Cotton ball is soft, used often, and its man mad pine cones came from trees, they give off a scent, but are mostly not used.
The temperature : 263.016 K
<h3>Further explanation</h3>
Combined with Boyle's law and Gay Lussac's law

P1 = initial gas pressure (N/m² or Pa)
V1 = initial gas volume (m³)
P2 = gas end pressure
V2 = the final volume of gas
T1 = initial gas temperature (K)
T2 = gas end temperature
P1=760 mmHg
V1= 4 L
T1 = 275 K
P2=704 mmHg
V1=4.13 L

PH = -log [H+]
pH = -log (1.0x10^-4) = -(-4) = 4 or A
To find average atomic mass, multiply each isotope's atomic mass with its relative abundance and add it all up.
15.012*0.1423 + 16.988*0.3348 + 19.177*0.5229 = 17.851 (5 s.f.)