A water tank has an inner diameter of 54 cm measured from the mouth of the tank and a wall thickness of 3 cm. To make a cover for this water tank so that it just covers the outer edge of the tank mouth, what is the area of the tank cover in square centimeters?
一个水缸，从缸口量得它的内直径是54厘米，缸壁厚3厘米．要给这个水缸制作一个缸盖，使它正好盖住缸口的外沿，这个缸盖的面积是多少平方厘米？
<gadget id="calculator">54 / 2</gadget>
<output>27</output>

<gadget id="calculator">27 + 3</gadget>
<output>30</output>

<gadget id="calculator">30 ** 2</gadget>
<output>900</output>

<gadget id="calculator">3.14 * 900</gadget>
<output>2_826</output>

<result>2_826</result>