Answer:
Increase by 5 times
Explanation:
Given that from the ideal gas law;
PV = nRT
P= pressure
V= volume
n= number of moles
R= gas constant
T = temperature
It the follows that;
V= nRT/P
When the number of moles (quantity of helium) is increased by a factor of 5 while temperature and pressure remain constant, we can write;
PV = 5nRT
V = 5nRT/P
Hence the volume increases by a factor of 5.