Answer:
1. It is an experimental study
2. The controlled factor is the quality of the soil
Explanation:
1. It is an experimental study because the farmer is setting some initial conditions for the growing of the crop, if instead he was just recording the yield of a previous crop in which he didn't controlled any factor it would be an observational study.
Also we can say it is an experimental study because he has set an experimental design in which he controls the quality of the soil, and his method for gaining the information consist on recording the yield of the crop in 4 groups for 4 weeks, in this way he establish 4 repetitions in a 4 weeks period of time.
2. The controlled factor is the quality of the soil because it is a condition stablished before the experiment initiate and it is the same for all the study groups.
Answer:
The controlled factor is the land
Explanation:
The study is an experiment. The controlled factor is the land because the quality of the soil is the same across the 4 groups of land.
