Which tank has a cylinder constant of 3.14?

The H tank is the correct choice as it has a cylinder constant of 3.14. This constant is crucial in calculating the duration of flow for oxygen tanks, as it relates the pressure in the tank to the flow rate and helps in determining how long the tank will last under specific usage conditions. Each type of tank, such as the E, G, and K tanks, has its own unique cylinder constants, which differ based on their size and design. Understanding the cylinder constants of various tanks is essential for paramedics to manage oxygen supplies effectively during patient care.