Letter of Credit Forum

I would like to ask very basic questions on L/Cs (in Indian context if it is)

1) Sight L/Cs - technically at sight but how much time is provided by banks to make the payment? 1 Week?

2) Usance L/Cs - Minimum & Maximum tenor allowed

3) How is pricing done for L/Cs? What are differnent kind of fees involved? (if answers varies for Sight/Usance/Usance Payable at Sight, please mention).

4) Give me closest example of the actual prices/fees of LCs to get a fair idea on how the prices looks like.

Please pardon my ignorance on the topic. Thanks a lot.