Factors can change between the time you place an order and the time of credit card charge authorization, which could affect the calculation of sales taxes.

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It authorizes the transaction and sends bits whizzing back, a 39, 000-kilometer roundtrip journey that involves five stops plus a calculation of how much to charge the merchant in fees and how to divvy up those fees among the banks.

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"This was clearly with prior calculation and design, " a component of the death penalty aggravated murder charge, Baumoel said.

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If the EPA uses the same calculation for fuel cells as for battery vehicles, whereby the energy used to charge the battery is counted and deducted from the mileage label, fuel cell vehicles would be rated at about 80 mpg.

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