Cover Letter

[tesco]

My sister has an interview tomorrow for a job through her school (COOP program). She has to take a cover letter and resume with her for the person interviewing her.
She already met the person a few days ago and got her first name, but not the last name.
It's now too late to call and find out her full name (if this is even appropriate to do anyway).

Is it alright to write
"Dear FirstName,

blah blah"

in a covert letter?

She could write dear madam but that sounds odd seeing as she met the lady already and knows her by first name.

[clocker]

A cover letter is a more personal form of the business letter and therefore, "Dear Firstname" is fine.

[tesco]

Thanks!