(44) Public water system --A system supplying water to a number of connections or individuals, as defined by current rules and regulations of the Texas Commission on Environmental Quality, 30 TAC Chapter 290.
According to studies backed by the department of energy, the average car will be at its advertised MPG at 55 mph. But as the speed increases: - 3% less efficient at 60 mph. - 8% less efficient at 65 mph.
The 'Q' rating on the tyre represents the speed rating and any  tyres that come with a 'Q' speed rating means that the manufacturer  recommends a maximum speed of 99mph.