"Alexa, Launch P. D. X. Bus Tracker."
"Alexa, Ask P. D. X. Bus Tracker for two two six six."
"Alexa, Ask P. D. X. Bus Tracker for help"
PDX Bus Tracker tells you arrivals for all buses for a given Stop ID. Invoke by calling Open PDX Bus Tracker, provide the Stop ID and it will respond with all Buses, Scheduled times and Next arrival times. Disclaimer; the app may not be suitable for all ages.