What is the surface area of a cylinder whose base radius is 8 cm and whose height is 15 cm?
一个圆柱的底面半径是8厘米，高是15厘米，它的表面积是多少平方厘米．
<gadget id="calculator">8 ** 2</gadget>
<output>64</output>

<gadget id="calculator">3.14 * 64 * 2</gadget>
<output>401.92</output>

<gadget id="calculator">2 * 3.14 * 8 * 15</gadget>
<output>753.6</output>

<gadget id="calculator">401.92 + 753.6</gadget>
<output>1_155.52</output>

<result>1_155.52</result>