Answer:
12 to 14
Explanation:
drain cleaners contain sodium hydroxide or potassium hydroxide which are strong bases . The pH value of sodium hydroxide and potassium hydroxide is 14 and 12 respectively on the pH scale. So, most drain cleaners have a pH of from 12 to 14, regardless of how much L there are.
I am pretty sure the correct answer is B.
It makes the most sense to me.
Answer : The correct option is, pressure.
Explanation :
The ideal gas equation is,

where,
P = pressure of the gas
V = volume of the gas
n = number of moles of gas
T = temperature of the gas
R = gas constant
The value of 'R' has several different values which are :




That means, the value of 'R' is different due the change in the pressure value and all the variables (temperature, volume and moles) are constant.
Hence, the correct option is, pressure.