See the answer below.
Work Step by Step
a) All flasks must have the same number of moles at the same Temperature, Pressure and Volume to be ideal gases. b) $160/16=10$ times heavier since both have the same number of moles. c) Flask C; since they all have the same number of moles, the one with the smaller mass has the smaller molecular weight and consequently the bigger root mean square speed and kinetic energy.