An online shop sells a certain calculator for P950 and charges P150 for shipping within Manila, regardless of the number of calculators ordered. Which of the following equations shows the total cost (y) of an order as a function of the number of calculators ordered (x)?

• A. y=(950 + 150)x
• B. y=150x+950
• C. x=950y+150
• D. y=950x+150