residents in a neighborhood determine the app...
residents in a neighborhood determine the approximate number of dandelions in each yard. then, they treat some yards with a weed - killing substance. the residents want to answer the question “about how many dandelions are in your yard?” to determine the effectiveness of the weed killer. from which group would it be best to take a sample? all residents of the neighborhood only residents who had their yards treated with weed killer only residents who did not have their yards treated with weed killer only residents who still have dandelions in their yards after treatment with weed killer
Answer
# Brief Explanations:
To determine the effectiveness of the weed - killer, we need to compare the number of dandelions before and after treatment. Sampling from residents who had their yards treated with weed - killer allows for this comparison. Sampling from all residents doesn't focus on the treatment effect. Sampling from non - treated residents or those with remaining dandelions doesn't give a full picture of the treatment's effectiveness.
# Answer:
only residents who had their yards treated with weed killer