Main products formed during a reaction of 1-methoxy naphthalene with hydroiodic acid are :

Consider the above reaction, the product 'X' and 'Y' respectively are :

In Tollen's test for aldehyde, the overall number of electron(s) transferred to the Tollen's reagent formula [Ag(NH₃)₂]⁺ per aldehyde group to form silver mirror is ___________. (Round off to the Nearest Integer).

10.0 mL of Na₂CO₃ solution is titrated against 0.2 M HCl solution. The following titre values were obtained in 5 readings :

4.8 mL, 4.9 mL, 5.0 mL, 5.0 mL and 5.0 mL

Based on these readings, and convention of titrimetric estimation the concentration of Na₂CO₃ solution is ___________ mM.

(Round off to the Nearest Integer).