A parent company settles the collection account balances of its subsidiaries once a week. (That is, each week it transfers any balances in the accounts to a central account.) The cost of a wire transfer is $12. A check costs $0.93. Cash transferred by wire is available the same day, but the parent must wait three days for checks to clear. Cash can be invested at 14% per year.

How much money must be in a collection account before it pays to use a wire transfer?

Please show all workings!