please give solution as soon as possible

3. Mr Karim is a Bangladeshi businessman and he wanted to import 50 tons of onion from Turkey. He contacted Mr Kuruls Osman, the owner of the Ruselsun Co. Ltd, who has a big onion company in Turkey and asked for 50 tons of onion. Mr Osman agreed to send him the goods and recommend opening a letter of credit. Mr Karim came to you to know the process of a letter of credit. Advise him. (15)