The ultrasound signal emitted by the external transducer calculates the fetal heart rate by counting the reflected signals that have?

Respuesta :

Answer:

high frequency sound waves

Explanation:

The fetal cardiac activity emits signal that comprises of high frequency sound waves. This signal is received only when it is converted into  a fetal heart rate tracing via computer. These signals are traced through transducers and are shown on the external monitor.