There is a bottle of "White Cat Disinfectant" on the trademark: 700g net content, 1:500 dilution for disinfection of tableware, kitchen supplies, and white clothes; 1:300 dilution for surface disinfection of refrigerators, telephones, etc.; For pollutants, mix 50g of this product with a basin of water. If this bottle of disinfectant is used to disinfect the surface of the refrigerator, how many kilograms of water should be used to dilute it after use.
有一瓶"白猫消毒液"商标上写着：净含量700g，餐具厨房用品、白色衣物消毒用1：500稀释液；冰箱、电话等表面消毒用1：300稀释液；肝炎、传染病患者的污染物用本品50g和一盆水混合．如果这瓶消毒液用于冰箱表面消毒，用完后大约要用多少千克水去稀释．
<gadget id="calculator">300 / 1_000</gadget>
<output>3/10 = around 0.3</output>

<gadget id="calculator">700 * (3/10)</gadget>
<output>210</output>

<result>210</result>