The data in the table were recorded during an investigation in which a paramecium was placed in a hypertonic salt solution.

\begin{tabular}{|c|c|}
\hline \multicolumn{2}{|c|}{Paramecium Contractile Vacuole Contractions} \\
\hline \begin{tabular}{c}
Salt concentration outside \\
paramecium
\end{tabular} & \begin{tabular}{c}
Contractions per \\
minute
\end{tabular} \\
\hline Very high & 2 \\
\hline High & 8 \\
\hline Medium & 15 \\
\hline Low & 22 \\
\hline Very low & 30 \\
\hline
\end{tabular}

Which statement correctly describes the bars on a bar graph representing the data?

A. The graph has five bars of equal height.
B. The graph shows that contractions decrease as salt concentration increases.



Answer :

To determine whether the bars on a bar graph representing the data are of equal height, we need to analyze the given data in the table.

The data in the table is as follows:

[tex]\[ \begin{array}{|c|c|} \hline \text{Salt concentration outside paramecium} & \text{Contractions per minute} \\ \hline \text{Very high} & 2 \\ \hline \text{High} & 8 \\ \hline \text{Medium} & 15 \\ \hline \text{Low} & 22 \\ \hline \text{Very low} & 30 \\ \hline \end{array} \][/tex]

If we are to graph this data on a bar graph, the height of each bar will correspond to the number of contractions per minute for each salt concentration level.

1. The "Very high" salt concentration corresponds to 2 contractions per minute.
2. The "High" salt concentration corresponds to 8 contractions per minute.
3. The "Medium" salt concentration corresponds to 15 contractions per minute.
4. The "Low" salt concentration corresponds to 22 contractions per minute.
5. The "Very low" salt concentration corresponds to 30 contractions per minute.

To see if all bars are of equal height, we need to check if the contractions per minute values are the same for all levels of salt concentration:

- 2 (for "Very high")
- 8 (for "High")
- 15 (for "Medium")
- 22 (for "Low")
- 30 (for "Very low")

Clearly, the values 2, 8, 15, 22, and 30 are different from each other.

Hence, not all values are the same, meaning the bars on a bar graph will have different heights. Therefore, the statement "The graph has five bars of equal height" is incorrect.

The correct statement is that the bars on the graph will have different heights.