Use the Rule of 78 to determine the unearned interest on a loan with these conditions.
$$\text{Unknown environment 'tabular'}$$ & $$\text{Unknown environment 'tabular'}$$ & $$\text{Unknown environment 'tabular'}$$ \
\hline$\mathrm{\$}860$ & 48 & 12 \
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\end{tabular}

The unearned interest is $\mathrm{\$}◻$.
(Round to the nearest cent as needed.)

Step 1 ：The Rule of 78 is a method used by some lenders to calculate the amount of interest a borrower must pay if they pay off their loan early. The rule is named after the sum of the digits 1 through 12 (the number of months in a year), which equals 78.

Step 2 ：The formula to calculate the unearned interest using the Rule of 78 is: Unearned Interest = $\frac{\text{{Remaining Payments}}\times (\text{{Remaining Payments}}+1)}{\text{{Total Payments}}\times (\text{{Total Payments}}+1)}$ * Finance Charge

Step 3 ：In this case, the Finance Charge is $860, the Total Number of Payments is 48, and the Remaining Number of Payments when Paid in Full is 12.

Step 4 ：Let's plug these values into the formula and calculate the unearned interest.

Step 5 ：Unearned Interest = $\frac{12\times (12+1)}{48\times (48+1)}$ * 860 = $57.04

Step 6 ：Final Answer: The unearned interest is $\boxed{{\displaystyle \mathrm{\$}57.04}}$