读合同的支付条款,回答问题 9) Terms of payment: By 100% Confirmed irrevocable Letter of Credit in favor of the Sellers to be available by sight draft to be opened and to reach China before MAY 1, 2018 and to remain valid for negotiation in China until the 15th days after the foresaid Time of shipment. All banking Charges out side China are for account of the Applicant. 问题: 1、该合同的支付方式是?(电汇/托收/信用证?) 2、该信用证是即期还是远期? 3、该信用证是否?(是/否) 4、信用证的受益人是谁? 5、该信用证议付有效的地点是哪个国家? 6、该信用证规定的交单有效时间为装运期后多少天?