Un camión de bomberos lleva una velocidad de 100 km/h y su sirena suena con una frecuencia de 900 Hz;  ¿qué frecuencia aparente escucha un observador, cuando lo ve acercarse?

c. rb

explanation:

the atomic radius of a chemical element is a measure of the size of its atoms, usually the mean or typical distance from the center of the nucleus to the boundary of the surrounding shells of electrons.

hello there!

your answer is a “generator”

a generator does not create energy but instead it transforms it.

it’s basically a motor working in reverse.