There is a house (flat roof) with a length of 6 meters, a width of 3.5 meters, and a height of 3 meters. The area of doors and windows is 8 square meters. Now it is necessary to paint its four walls and top surface. If 5 kilograms of cement is needed per square meter, how many kilograms of cement are needed in total?
有一间房屋(平顶)，长6米，宽3.5米，高3米，门窗面积是8平方米，现在要粉刷它的四壁和顶面．如果每平方米需要水泥5千克，共需要水泥多少千克？
<gadget id="calculator">6 * 3 * 2</gadget>
<output>36</output>

<gadget id="calculator">3.5 * 3 * 2</gadget>
<output>21</output>

<gadget id="calculator">6 * 3.5</gadget>
<output>21</output>

<gadget id="calculator">21 - 8</gadget>
<output>13</output>

<gadget id="calculator">36 + 21 + 13</gadget>
<output>70</output>

<gadget id="calculator">5 * 70</gadget>
<output>350</output>

<result>350</result>