The number of electrons involved in redox reactions when $1$ Faraday of electricity is passed through an electrolyte in solution is

Faraday's $2^{nd}$ law of electrolysis states that the mass of a substance deposited at an electrode is directly proportional to its:

$250 \ mL$ of a waste solution obtained from the workshop of a goldsmith contains $0.1 \ M \ AgNO_3$ and $0.1 \ M \ AuCl$. The solution was electrolyzed at $2 \ V$ by passing a current of $1 \ A$ for $15 \ minutes$. The metal/metals deposited will be
$(E^0_{Ag^+/Ag} = 0.80 \ V, E^0_{Au^+/Au} = 1.69 \ V)$

When $0.1 \ mol$ of $MnO_4^{2-}$ is oxidized,the quantity of electricity required to completely oxidize $MnO_4^{2-}$ to $MnO_4^-$ is $........ \ C$.

When $9.65 \ C$ of electricity is passed through a solution of silver nitrate (atomic weight of $Ag = 108$),the amount of silver deposited is $............ \ mg$.

The cost of energy required to deposit $1 \ g$ of $Mg$ is $5.00$ rupees. What is the cost to deposit $10 \ g$ of $Al$? (Atomic mass of $Al = 27, Mg = 24$)