There are two cylinders with a base diameter of 8 cm. One of the cylinders is 3 cm in height and the other is 7 cm in height. If these two cylinders are connected to form a cylinder, what is the surface area of it?
有两个圆柱，底面直径都是8厘米，其中一个圆柱的高是3厘米，另一个圆柱的高是7厘米，把这两个圆柱连接成一个圆柱，它的表面积是多少．
<gadget id="calculator">3 + 7</gadget>
<output>10</output>

<gadget id="calculator">3.14 * 8 * 10</gadget>
<output>251.2</output>

<gadget id="calculator">8 / 2</gadget>
<output>4</output>

<gadget id="calculator">4 ** 2</gadget>
<output>16</output>

<gadget id="calculator">3.14 * 16 * 2</gadget>
<output>100.48</output>

<gadget id="calculator">251.2 + 100.48</gadget>
<output>351.68</output>

<result>351.68</result>