Wang Fei deposited 20,000 yuan in the bank for one year at an annual interest rate of 2.50%. How much is the pre-tax interest that Wang Fei should get when it expires?
王飞把二万元钱存入银行，定期一年，年利率2.50%．到期时，王飞应得税前利息是多少元．
<gadget id="calculator">2.5 / 100</gadget>
<output>0.025</output>

<gadget id="calculator">20_000 * 0.025 * 1</gadget>
<output>500</output>

<result>500</result>