Balance of settlement reserve for the current day = balance of settlement reserve for the previous trading day+trading deposit for the previous trading day-trading deposit for the current day+profit and loss for the current day+deposit and withdrawal-handling fee, etc. This problem does not consider deposits, withdrawals and handling fees.

(balance of settlement reserve on the previous trading day+trading margin on the previous trading day) = capital equity of the customer on the previous trading day = margin+profit and loss.

Liu's profit and loss in June 1: (2050-2000)× 10 tons× 20 lots = 10000 yuan.

Liu's capital interest in June1=100000+10000 =10000.

At the time of settlement on June 2, the contract profit and loss of soybeans bought in June1:(2060-2000) ×10 × (40-20) =12000 yuan;

Profit and loss of soybean contract bought on that day: (2060-2040) ×10× 8 =1600 yuan;

Trading margin of the day: 2060×10× (40-20+8 )× 5% = 28,840 yuan;

Therefore, the balance of reserve fund for Liu's account settlement on June 2 is:110000+12000+1600-28840 = 94760 yuan.