To make a cuboid fish tank without a cover, the length is 60 cm, the width is 40 cm, and the height is 50 cm. How many square centimeters of glass do you need at least?
做一个无盖长方体鱼缸，长60厘米，宽40厘米，高50厘米，至少需要多少平方厘米的玻璃？
<gadget id="calculator">60 * 40</gadget>
<output>2_400</output>

<gadget id="calculator">60 * 50</gadget>
<output>3_000</output>

<gadget id="calculator">40 * 50</gadget>
<output>2_000</output>

<gadget id="calculator">3_000 + 2_000</gadget>
<output>5_000</output>

<gadget id="calculator">5_000 * 2</gadget>
<output>10_000</output>

<gadget id="calculator">2_400 + 10_000</gadget>
<output>12_400</output>

<result>12_400</result>