Assuming that the 2007 Ford has an average fuel efficiency of 20 miles per gallon (mpg) and the distance from Philadelphia to Ocean City, Maryland is approximately 100 miles, the car will need approximately 5 gallons of gas to make the trip.
With the current average gas price in Philadelphia being around $4.00 per gallon, it would cost approximately $20 to fill up the tank and complete the trip.
It's important to note that gas prices can fluctuate over time, so the actual cost may be different. Additionally, the fuel efficiency of the vehicle and the traffic conditions can also affect the amount of gas needed for the trip.