The circular flower bed in the flower garden in the park has an outer circumference of 78.5 meters and a ring width of 1.2 meters. Find the area of this flower bed.
公园内花圃中的圆形花坛，外圆周长78.5米，环宽1.2米．求这个花坛的面积．
<gadget id="calculator">78.5 / 3.14 / 2</gadget>
<output>12.5</output>

<gadget id="calculator">12.5 ** 2</gadget>
<output>156.25</output>

<gadget id="calculator">12.5 - 1.2</gadget>
<output>11.3</output>

<gadget id="calculator">11.3 ** 2</gadget>
<output>127.69</output>

<gadget id="calculator">156.25 - 127.69</gadget>
<output>28.56</output>

<gadget id="calculator">3.14 * 28.56</gadget>
<output>89.6784</output>

<result>89.6784</result>