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5. If the total cost of manufacturing q units of a product is C(q) =11q'-25q* + 400q+38 (in dollars), use marginal analysis to estimate the cost of manufacturing the 9th unit. A. $2,343 B. $2,234 C. $2, 112 D. $2,000A debt of $5,000 due in three years from now and $4.000 due in four years from now is to be repaid by : a payment of $3000 now and another payment of x dollars one year from now. If the annual interest rate is 8% compounded quarterly, how much is the payment x, correct to 2 decimal places? A. $5,339.57 B. $5,132.78 C. $4,442.36 D. $4,174.13