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.
B the most well known chemicals inside cigarettes would includen carbon monoxide and tar.
Drinking alcohol during pregnancy can indeed cause severe damage to an developing embryo. This is completely true. This is also the reason why pregnant women should avoid drinking alcohol and why it's not good to do so for them.
