To prepare a pesticide, the ratio of powder to water is 1:500. The existing medicinal powder is 3.6 kg, how much water is needed to prepare this pesticide?
配制一种农药，药粉和水的比是1：500．现有药粉3.6千克，配制这种农药需要水多少千克？
<gadget id="calculator">3.6 / 1</gadget>
<output>3.6</output>

<gadget id="calculator">3.6 * 500</gadget>
<output>1_800</output>

<result>1_800</result>