A scientist planted seeds in $4$ sections of soil for an experiment. Not all of the seeds grew into plants. After $20$ days, the scientist counted the number of plants in each of the $4$ sections. The results are shown in the table. Use the data in the table to determine approximately how many plants grew per square foot. Explain or show how you determined your approximation. Let $y$ be the number of plants expected to grow in $x$ square feet. Write an equation the scientist could use to model the relationship between $y$ and $x$ . Provide your approximation, explanation, and equation in the space provided.