which graph or graphs appear to show a sinusoid ?
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Answer:
D
Step-by-step explanation:
Sinusoid graphs look like regular waves.
It is obvious that only I and III look like waves.
II is known as a stepwise function.
Option: D is the correct answer.
D. I and III only
From the graph that is provided to us we observe that the graph I is a sinusoidal graph since it is similar to a graph of sine graph.
Also, the graph II is not a continuous graph and hence it can't be a graph of sinusoidal graph.
Also, graph III is similar to a graph of sine function and hence it represent a graph of a sinusoidal graph.