stoichiometry

A mixture of CO and CO₂ when treated with I₂O₅ , gives I₂ vapour according to following eqn. :
5CO + I₂O₅ - > 5CO₂ + I₂
I₂ vapour was separated nd treated with HClO₄ and resultant HIO₄ reqd. 0.001 moles of glycerol ( CH₂OHCHOHCH₂OH ) for complete oxidn.
After treatment with I₂O₅ and removal of I₂ , the mixture was treated with excess of 0.1 N NaOH soln. Finally this soln. reqd. 20 ml of 1N HCl to reach the end pt. using phenolphthalein as indicator followed by using methyl orange as indicator after 1st end pt. and 10 ml of further HCl was consumed . Calculate the volume of NaOH used and % mole of CO₂ in original mixture.