A and B jointly produce a kind of parts, A takes 8 hours to produce, and B takes 6 hours to produce, a total of 520 pieces are produced. It is known that B's 5-hour workload is equal to A's 2-hour workload, how many parts does B produce per hour?
甲、乙二人共同生产一种零件，甲生产了8小时，乙生产了6小时，一共生产了520个．已知乙5小时的工作量等于甲2小时的工作量，乙每小时生产多少个零件？
<gadget id="calculator">8 / 2</gadget>
<output>4</output>

<gadget id="calculator">4 * 5</gadget>
<output>20</output>

<gadget id="calculator">20 + 6</gadget>
<output>26</output>

<gadget id="calculator">520 / 26</gadget>
<output>20</output>

<result>20</result>