A and B are either of the same age or A is older than B. C and D are of the same age or D is older than C. B is older than C. Which of the following statements is definitely correct?

Five students graduated from a college, not all in the same year, after each studied for four years. Batchmates Jiten and Anwar were junior to Ramesh but senior to Prakash and Sam. If Ramesh had left the college before Jiten took admission, then it is certain that:

5 boys took part in a race. Raj finished ahead of Mohit but behind Gaurav. Ashish finished ahead of Sachin but behind Mohit. Who won the race?