How long should the ITX function with a fully charged battery pack?

The ITX is designed to function effectively for extended periods when using a fully charged battery pack. The correct answer is based on the specifications provided by the manufacturer, which indicates that a fully charged battery can sustain the device for up to 19 hours under normal operating conditions. This information is crucial for users who need to plan their usage effectively, ensuring that they can rely on the device for a significant amount of time without needing to recharge.

In contrast, the other options suggest longer operating times that exceed the manufacturer's specifications. While it's important to consider variations in battery performance based on usage and environmental factors, the most accurate estimate, which aligns with the technical details of the device, is that it can last up to 19 hours on a single charge. Therefore, this choice stands out for its accuracy and practical implications for users.