Suppose you are standing at rest as you watch a train approach you with a whistle that has a frequency of 1600 Hz. Describe the pitch or pitches you hear as the train approaches, passes in front of you, and travels away from you.

This is the answer of your question

We have no idea what the graph shows, or why it may be accurate,  because we can't see the graph.on a different subject, choice ' d ' is the only true statement among the choices.

Aand b antarctica is a north pole.  field lines enter earth near the north pole.the magnetic pole near antarctica is a north pole.compasses point toward a magnetic pole that is a north pole.field lines circle earth from east to west.a compass can lead a hiker to the geographic north pole.