Clark and Phil are each running to raise money. The amount of money (y), in dollars, they each raise is based on the distance (x), in miles, they each run. Clark has an initial donation that he has received regardless of how many miles he runs. The graphs model the amount of money each will raise based on the distance they each run. What is the unit rate for the person for whom the amount of money and the number of miles are proportionally related? A) $5.00 per mile B) $7.50 per mile C) $15.00 per mile D) $30.00 per mile