Final answer:
The mark-up amount is calculated by subtracting the wholesale price from the selling price, which is $34.55, corresponding to option a.
Step-by-step explanation:
The student asked to find the mark-up amount when a florist buys a dozen roses for a wholesale price and sells them at a higher price. To calculate the mark-up, we subtract the wholesale price from the selling price. The wholesale price given is $12.95, and the selling price is $47.50. To find the mark-up amount, we need to calculate the difference between the selling price and the wholesale cost. The selling price of a dozen roses is $47.50 and the wholesale cost is $12.95. Using these numbers:
Mark-up Amount = Selling Price - Wholesale Price
Mark-up Amount = $47.50 - $12.95
Mark-up Amount = $34.55
Therefore, the mark-up amount is $34.55, which matches option a.