RUNNING Randi has been training for a marathon, and it is important for her to keep a constant pace. She recorded her time each mile for the first several miles that she ran. - At 1 mile, her time was 10 minutes and 30 seconds. - At 2 miles, her time was 21 minutes. - At 3 miles, her time was 31 minutes and 30 seconds. - At 4 miles, her time was 42 minutes. Part A Write a function to represent her sequence of data. Use \( n \) as the variable. f(n) \( = \) Part B How long will it take her to run a whole marathon? Round your answer to the nearest thousandth if necessary. (Hinda marathon is 26.2 miles.) hours

**Part A** To represent Randi's sequence of data, we observe that her cumulative time increases by 10.5 minutes for each additional mile. This indicates a linear relationship between the number of miles run and the total time taken. The function \( f(n) \) can be expressed as: \[ f(n) = 10.5n \quad \text{minutes} \] where: - \( n \) is the number of miles run. - \( f(n) \) is the total time in minutes after running \( n \) miles. **Part B** To determine how long it will take Randi to run a full marathon (26.2 miles), we use the function from Part A: \[ \text{Total Time} = f(n) = 10.5n \] Plugging in \( n = 26.2 \): \[ \text{Total Time} = 10.5 \times 26.2 = 275.1 \text{ minutes} \] To convert minutes into hours: \[ \text{Total Time in Hours} = \frac{275.1}{60} \approx 4.585 \text{ hours} \] **Final Answer:** **Part A** \[ f(n) = 10.5\,n \quad \text{minutes} \] **Part B** Randi will take approximately \( 4.585 \) hours to run the marathon.