Help! I need help figuring out the GPA I will need.?

Ok, I am an undergraduate at The University of Texas-Pan American seeking to gain acceptance into the Coordinated Program in Dietetics in hopes of becoming a Registered Dietitian (RD). I am looking at applying to the program by the spring of 2015. So far I have completed 38 credit hours with a GPA of 2.74.(It's horrible, I know, I was lost, was not goal oriented, did not know what I wanted to study and was not as determined as I am now) My goal is to obtain a 3.5 GPA by the end of the Fall 2014 Semester. In order to do that, I will be taking 14 credit hours in the Spring of 2014, 7 hours in Summer I 2014, and perhaps 15 hrs in the Fall of 2014. What kinds of grades should I shoot to get (I know most likely I would need all As, but is there a little cushion to get a B or two?) in order to get that 3.5 by the end of fall 2014? How can i calculate what I need to achieve that 3,5 GPA? Thanks!