The BEST action for the salesperson to take in order to view weather forecasts while travelling is to configure less frequent location checks using cellular location services. This will reduce the amount of battery power consumed by the weather application, as it will not be constantly accessing the device's GPS or location services. Option A, enabling the GPS service, would drain the battery quickly. Option B, manually entering office locations, would be inconvenient and time-consuming. Option D, using the offices' Wi-Fi IP addresses as the geolocation mechanism, may not work when the salesperson is outside of the office.