Answer: Unas amigas, unos maestros
Explanation: Unas is the plural version of una. If it was amiga then it would be unacceptable amiga, when it has an A at the for words like amiga and hermana, its feminine, so if we're talking about some girl friends, it would be unassuming amigas, if it was for guys it would be unos amigos. Hope this helps!!!