Final answer:
The design of the investigation in the second growing year could have been altered based on previous results, introducing changes such as optimized pest control methods or different agricultural practices, resulting in varying outcomes.
Step-by-step explanation:
To ascertain how the design of an investigation could lead to different results in the second growing year, we must understand the factors influencing the outcome. In this case, it’s possible that interventions like pest resistant cultivars, interplanting practices, and targeted pesticide application were adapted on the basis of previous year's findings. For example, the use of ladybug beetles could have been optimized or modified in the second year, potentially making the pest control method more effective against tomato hornworms or other pests. A difference in the number of tomato plants used, the effectiveness of insecticide treatments, or the severity of pest infestation could also contribute to different outcomes.
Researchers may have involved techniques such as selective pesticide placement, which has the secondary benefit of preserving predators beneficial to the crops, like ladybug beetles. Similarly, modifications in the overall pest management strategy, such as introducing pest resistant cultivars or changing intercropping patterns, could either reduce the pest pressure or enhance pest control efficacy and lead to the changes in the results of the second growing year.