Rewrite the entire sentence replacing the indirect object with an indirect object pronoun.
Nosotros hablamos por teléfono con la <u>maestra</u>.
Answer : Nosotros le hablamos por teléfono.
Explanation: The indirect object is "la maestra", that is third singular person, so the indirect object pronoun has to be in the third singular person too, "le".
Hope this helps!
Answer:
A child ties a rope to a stone and spins it evenly at 7 radians/ second. ( This is the translation in english to your sentence).