Answer:
296.43 K is the temperature of a vessel when pressure reads 1.250 atm.
Explanation:
At STP, when pressure is 1.000 atm the value of temperature is 273,15 K.
If the pressure at temperature T reads as 1.250 atm.


Applying Gay Lussac's law:
(At constant volume)


296.43 K is the temperature of a vessel when pressure reads 1.250 atm.
Im not really sure but my best guess is d 52.8%
I suck at chemistry but i have a friend that can help
I am pretty sure it is nitrogen, oxygen, carbon and hydrogen.