What is the net annual cost of the following chequing accounts?

a$.$ Monthly fee, $$2\mathrm{.}50$; processing fee, $30$ cents per cheque; cheques written, an average of $2$ a month; $$0\mathrm{.}60$ per debit

transaction over the $20$ debit transactions per month that are free with an average of $40$ per month made. $($Round your final

answer to $2$ decimal places. Omit the $"$$$"$ sign in your response.$)$

Annual cost $

b$.$ Interest earnings of $6$ percent with a $$500$ minimum balance; average monthly balance, $$600$; monthly service charge of

$$18$ for falling below the minimum balance, which occurs three times a year $($no interest earned in these months$).($Round your

final answer to $2$ decimal places. Omit the $"$$$"$ sign in your response.$)$

Net cost $