Huan made a chart to study for an exam about radio waves.

\begin{tabular}{|l|l|}
\hline
\multicolumn{1}{|c|}{[tex]$X$[/tex]} & \multicolumn{1}{|c|}{[tex]$Y$[/tex]} \\
\hline
- Changes the frequency of a wave & - Changes the height of a wave \\
- Is used by cell phones to transmit data & \begin{tabular}{l}
- Is used by television stations for \\
pictures
\end{tabular} \\
\hline
\end{tabular}

Which headings best complete the chart?

A. [tex]$X$[/tex]: Phase \\
[tex]$Y$[/tex]: Pulse

B. [tex]$X$[/tex]: Pulse \\
[tex]$Y$[/tex]: Phase

C. [tex]$X$[/tex]: AM \\
[tex]$Y$[/tex]: FM

D. [tex]$X$[/tex]: FM \\
[tex]$Y$[/tex]: AM



Answer :

To determine the correct labels for the given chart, let's carefully analyze the descriptions for each column and match them with the appropriate radio wave terms.

For column [tex]$X$[/tex]:
- "Changes the frequency of a wave"
- "Is used by cell phones to transmit data"

For column [tex]$Y$[/tex]:
- "Changes the height of a wave"
- "Is used by television stations for pictures"

From our knowledge of AM (Amplitude Modulation) and FM (Frequency Modulation):
- AM involves changing the height (amplitude) of the wave, which corresponds to the descriptions for column [tex]$Y$[/tex].
- FM involves changing the frequency of the wave, which corresponds to the descriptions for column [tex]$X$[/tex].

Therefore, the correct headings for the chart should be:
- For [tex]$X$[/tex]: FM (Frequency Modulation)
- For [tex]$Y$[/tex]: AM (Amplitude Modulation)

Thus, the best headings that complete the chart are:
```
X: FM
Y: AM
```