The school is going to use the holiday time to paint the classrooms. It is known that each classroom is 8m long, 6m wide, and 3.5m high, and the area of doors, windows and blackboards is 18m**2. If 0.2 kilograms of paint is used per square meter, how many kilograms of paint will be used to paint the walls and ceiling of a classroom?
学校准备用假期的时间粉刷教室．已知每间教室长8m，宽6m，高3.5m，门窗与黑板的面积是18m**2．如果每平方米用涂料0.2千克，粉刷一间教室的四壁和天花板一共要用涂料多少千克？
<gadget id="calculator">8 * 6</gadget>
<output>48</output>

<gadget id="calculator">8 * 3.5</gadget>
<output>28</output>

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

<gadget id="calculator">28 + 21</gadget>
<output>49</output>

<gadget id="calculator">49 * 2</gadget>
<output>98</output>

<gadget id="calculator">98 - 18</gadget>
<output>80</output>

<gadget id="calculator">48 + 80</gadget>
<output>128</output>

<gadget id="calculator">128 * 0.2</gadget>
<output>25.6</output>

<result>25.6</result>