英语翻译Suppose you have purchased a non-refundable plane ticket

英语翻译
Suppose you have purchased a non-refundable plane ticket and,at the last moment,you cannot take the trip.You can,however,sell the ticket.If you paid $700 for the ticket,the cost of sending the ticket to someone through overnight mail is$20,and you spend $10 on a courier to get the ticket to the post office forovernight delivery,what is the minimum you should accept for the ticket?
a.$700 because that is what the ticket cost.b.$720 because that is the cost of the ticket and of getting it to the buyer.c $730 because that is the total cost of the ticket and getting it to the buyer.d.More than $730,so that you can make a profit.e.$30 because the $700 is a sunk cost.
应该是选e 然后题目后半部分有点看不懂是怎么回事