Question 5(d)
[Maximum number: 1]
Acid rain has negative effects on many ecosystems.
The second group of students placed 100 seeds in each of five Petri dishes, labelled 1 to 5. Group 2 used the same range of pH values as group 1.
They recorded the percentage of seeds that had germinated after 72 hours.
Their results are shown in Table 5.2.

Table 5.2
The teacher thought that group 2 had forgotten to add the sulfuric acid to one of their Petri dishes.
Suggest which Petri dish was not set up correctly.
