Dental operatory disinfectant

A dental assistant (DA) calculates the number of ounces (oz) of disinfectant required to clean the dental operatory between patients. He handpiece, 1/4 oz for the high-speed handpiece, %2 oz for the light, and ½ oz uses 13 oz of disinfectant for the dental chair, ½ oz for the low-speed for the dental cart. What is the total amount of disinfectant used?