B.com(hons.) 1st year improvement-sol.please help

i am a third year b.com(hons.) student,currently doing my graduation from school of open learning.i want to know if i can reappear in some of my first year(part 1) examinations in my 2012 exams along with my third year(part 3) examinations.i really want to increase my percentage.please comment on my query