Cut a square piece of paper 4 times horizontally and 6 times vertically, and cut it into 35 rectangular pieces of paper with the same shape and size as large as possible. Then cut such a rectangular piece of paper into as large as possible small square pieces of equal area. If the side length of the small square is 2 cm, what is the area of the rectangular piece of paper? Explain why.
将一张正方形纸片，横着剪4刀，竖着剪6刀，裁成尽可能大的形状大小一样的35张长方形纸片．再把这样的一张长方形纸片裁成尽可能大的面积相等的小正方形纸片．如果小正方形边长为2厘米，那么长方形纸片的面积应为多少平方厘米？说明理由．
<gadget id="calculator">2 * 5</gadget>
<output>10</output>

<gadget id="calculator">10 * 7</gadget>
<output>70</output>

<gadget id="calculator">70 * 70</gadget>
<output>4_900</output>

<result>4_900</result>