新加坡海外贸易公司（OVERSEAS TRADE COMPANY, 100 JULAN SULTAN, #01-20 SULTAN PLAZA, SINGAPORE 0719）与上海机械进出口公司(SHANGHAI MACHINERY IMPORT & EXPORT CORP. 383. Jiangning Road, Shanghai China)达成销售协议，其中协议第三条规定：除双方另有协议外，价格按CIF条件包括佣金3%；保险按发票金额的110%投保一切险和战争险，以现行中国保险条款为准；支付方式为不可撤销即期议付信用证。2007年12月间，新加坡海外贸易公司来电洽购货号727金星牌彩色电视机5000台，型号SC374，制式PAL/BG，220伏、50赫兹，双圆头插座带遥控（Gold Star Brand Colour Television Set, Model SC374, PAL/BG System, 220V 50Hz, 2 round pin plug, with remote control）；纸箱装（内用发泡塑料成型填充），每箱1台。以下是新加坡海外贸易公司与上海机械进出口公司往来电文： （1） Dec. 4th (incoming)：Gold Star Brand Colour Television set, model sc374, pal/bg system, 220v 50hz, 2 round pin plug, with remote control art 727 please fax present price available quantity for shipment February 2008 （2） Dec. 5th (outgoing) Yours fourth gold star brand colour television set art 727 in cartons of one set each reference price US Dollars 80.00 per set CIFc3 Singapore March shipment（3）Dec. 6th(incoming)：Yours fifth interested in 5000 sets CIFc5 February shipment please offer（4）Dec. 7th (outgoing):Yours sixth offer subject reply here tenth 4000 sets USD80.00 per set CIFc3 Singapore March shipment irrevocable sight L/C（5）Dec. 9th(incoming)：Yours 7th 5000 sets USD 72.00 CIFc5 Februbry shipment Credit 60 days Sight reply immediately（6）Dec. 10th (outgoing):Market tends upward demand keen your price too low regret unable counter offer（7）Dec. 12th(incoming):Yours 10th bid 5000 sets USD76.00 CIFc5 per set insurance amount 120 percent of CIF invoice value Feb. Shipment Credit 60 days Sight please reply before fourteenth（8）Dec. 13th(outgoing):Yours 12th we can only supply 4800 sets transported in 40’ containers of 800 cartons each best USD78.00 per set 30 days Sight Credit reply here 15th（9）Dec. 15th(incoming):Yours 13th accepted L/C opening by us please send us contract immediately（10）Dec. 16th(outgoing):Yours fifteenth S/C No. 0786335 airmailled
请将前五份电文译成中文。（10分）
