Which word is the singular form of unas pizarras? . una pizarra. un pizarra. uno pizarra. unas pizarra

Ayúdame con esta tarea de español lo necesito urgentemente

Choose the sentence that accurately expresses a hurt back. me duele la mano. me duele la espalda. me duele el cuello. me duele el brazo.

In the diagram, which must be true for point d to be anorthocenter? o be, cf, and ag are angle bisectors. be 1 ac, ag 1 bc, and cf 1 ab. be bisects ac, cf bisects ab, and ag bisects bc. be is a perpendicular bisector of ac, cf is aperpendicular bisector of ab, and ag is a perpendicularbisector of bc.