Sandra wanted to test the effectiveness of various kitchen cleaners, so she performed the following experiment. First, she prepa
red five agar plates with the same bacterial density (i.e., the same number of bacteria per plate). Then, she coated the entire agarose surface of one plate with 5 mLs of a particular kitchen cleaner. Finally, she repeated this step three more times using three other kitchen cleaners. Her results appear in the data table below. Plate # of Bacterial Colonies Untreated Plate 24 Cleaner 1 22 Cleaner 2 8 Cleaner 3 12 Cleaner 4 4 Which graph below best represents Sandra's data?
The most effective cleaners will grow the fewest bacteria. Since cleaners 1 and 3 grew considerably less bacteria than the control (the untreated plate), they are the most effective cleaners.
