A state park charges $5 per car plus $1 per person as an admission fee. The total charged for a car with x people is f(x) = x + 5. How will the graph of this function change if the per car charge is changed to $8 per car? The line will shift vertically down by $3. The line will shift vertically up by $3. The line will shift vertically up by $8. The line will shift vertically down by $8.