What subject pronoun would you use when talking to your teacher?

ellas
vosotras
ella
usted

Ella because it is formal and when talking to an adult or elder you speak formal

B. la madre le lavó las manos

Muchas playasanswer: muchas playas'the area's surf beaches include playa santa teresa and playa mal país in the south, and playa grande, in las baulas national marine park, in the north. leatherback turtles nest and hatch at playa grande.'