I think the answer is unas
Because if you putter together is
Unas palabras because the word end in s and the other word end in s too so is unas
It would be; Buenas tardes, Maestra!
Which in English it means; Good afternoon, Teacher!
Hope that helps too :D
Answer:
Van a escuchar música
Explanation:
Los sábados, Mariana y Carlo van a escuchar música con sus amigos
Andrea esta mirando los tazones
Andrea mira los tazones