What grades do I need to get my GPA to 3.0 or higher?

My GPA right now is 2.7, my marks are B+, B, B-, C(6 creds), C(3 creds), B(3 creds) , B(3 creds), B(3 creds), B(3 creds). If I retake the two C's and 4 B's, what grades would I need to get up to a 3.0 or higher?