Let's analyze the given data and the statements to determine which one correctly describes the bars on a bar graph representing the data.
The given table shows:
[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]
Now let's check each statement one by one against this data:
1. The graph has five bars of equal height.
- If all bars were of equal height, each value in the table would be the same. However, the contraction rates differ significantly: 2, 8, 15, 22, and 30. Hence, this statement is false.
2. The bars range from tallest for very high concentration to shortest for very low concentration.
- For very high concentration, the contractions per minute are 2, which is the lowest value. For very low concentration, the contractions per minute are 30, which is the highest value. Therefore, the bars will range from shortest for very high concentration to tallest for very low concentration. This statement is false.
3. The bar for very low concentration is twice the height of the bar for medium concentration.
- The contractions per minute for very low concentration are 30, and for medium concentration, it is 15. 30 is indeed twice 15. This statement is true.
4. The bar for very high concentration is five times the height of the bar for very low concentration.
- The contractions per minute for very high concentration are 2 and for very low concentration are 30. 2 is not five times 30; rather, it is much less. This statement is false.
Therefore, the statement that correctly describes the bars on a bar graph representing the data is:
The bar for very low concentration is twice the height of the bar for medium concentration. This corresponds to statement 3.
