翻译下列条款 TERMS OF PAYMENT: 30% T/T in advance,70%at 30days after B/L date opened through a hank acceptable to the seller valid for deferred payment in China until 20 Nov.2007. (2) 回答下列问题 ①受益人是否一定要向银行提交汇票?为什么? ②假如该条款的付款时间改为“at 30 days after sight”,对浙江有限公司是否有利?为什么?