A sales clerk enters a customer's six-number customer account. The computer program uses the first five numbers to calculate a sixth number. This resulting number is then compared to the sixth number entered by the sales clerk. This is an example of a:.1. Valid character test2. Missing data test3. Reasonableness test4. Checklist

4. Checklist

Explanation:

Option A is wrong because it requires character by character tests to validate the result.

Option B is wrong because the sales clerk has already posted all the data. Therefore, there is not necessary to test for missing data.

Option C is wrong because the Reasonableness test is doing for auditing purposes.

Option D is correct because it can compare one list with another. With the help of a checklist program, the number is compared to the last number entered to the clerk.

answermarginal cost;

of the three mortgage options that demarco and tanya have to choose from, the balloon payment mortgage would be their best option, over adjustable payment and fixed payment plans.ultimately, the balloon payment plan would save demarco and tanya overall, in interest, would cost less monthly, and they would only have to make these payments for 8 years, opposing to 30 years for adjustable or fixed payment plans. 

overall, demarco and tanya would save $80,811 if they chose balloon payments over fixed payments, and would save $116,711 if they choose balloon payments over adjustable payments. benefits with choosing fixed payments over adjustable payments is that, in the end, the payments will still be $836.30 a month, while with adjustable payments, the initial monthly payments will be $763.38 to $1082.70 a month, ultimately leading to a more costly purchase. benefits with choosing fixed payments over balloon payments are not present. benefits in choosing adjustable payments over is that it has a lower interest rate, and starts with lower monthly payments initially. benefits in choosing adjustable payments over balloon payments include a lower interest rate, and lower initial monthly payments. benefits in choosing balloon payments over fixed payments include lower interest rates, lower overall price, lower monthly payments, takes less time to pay off, and does not require a downpayment. benefits in choosing balloon payments over adjustable payments include, lower monthly payments (when averaged), takes less time to pay off, and lower overall price.

hence, option c, balloon payments, is the best option for demarco and tanya to make this purchase, for it will save them a minimum of $80811, and a maximum of $116,711.