Which of the following options correctly represent the increasing order of number of O atoms in the following samples? 

(P) 1.8 gm of glucose 

(Q) 1 gm-atom of oxygen. 

(R) Mixture of ozone and oxygen gas having total 5 millimoles of the two gases.

(S) Mixture of ${\mathrm{CO}}_{\left(\mathrm{g}\right)}$ and ${\mathrm{NO}}_{\left(\mathrm{g}\right)}$ having total 20 millimoles of the two gases.