classroom is 10m long, 7m wide, and 4m high. It is necessary to paint the roof and surrounding walls of the classroom. The area excluding doors, windows and blackboards is 28 square meters. How many square meters is the painted area?
一间教室长10m，宽7m，高4m，要粉刷教室的屋顶和四周墙壁，除去门窗和黑板的面积28㎡，粉刷的面积是多少平方米？
<gadget id="calculator">10 * 7</gadget>
<output>70</output>

<gadget id="calculator">10 * 4 * 2</gadget>
<output>80</output>

<gadget id="calculator">7 * 4 * 2</gadget>
<output>56</output>

<gadget id="calculator">56 - 28</gadget>
<output>28</output>

<gadget id="calculator">70 + 80 + 28</gadget>
<output>178</output>

<result>178</result>