Question

solve q.no.3 plzzzz with steps

Answer 1

Effusion is process in which gas is escaped from container having a tiny hole into an evacuated space. According to kinetic theory of gases, lesser is the mass, more will be the speed of gas because most probable speed of its molecules is higher. 
Graham's Law of Diffusion states that the rate of effusion is directly proportional to the speed of the gaseous molecules and inversely proportional to the square root of  molar mass.
Rate of Effusion α speed α 1M√M=molar mass
In the given question, mole ratio of He : CH​4 : SO2 = 1 :2 : 3
Molar mass of He = 4 g
Molar mass of CH4 = 16 g
Molar mass of SO2= 64 g

4:16:64
by using formula of effusion
He: CH4:SO2
will be 4:2:1

Answer 2

Please refer attachment