Recently I received a positive reply from the professor regarding summer research internship. How should I go on writing a mail to ask about the stipend and any prerequisite knowledge I should have before starting the internship?
Something along the lines of:
Thank you for your offer of a summer research internship. Is there a stipend associated with this and if so, how much is it?
Also is there anything else I should know before starting? Do I need to do some preliminary research of my own?
should be adequate.
Don't be afraid to come straight to the point. It's of benefit to you both to have clear communications.