Generally, candidates avoided this question, thus rendering it unpopular. Only few quoted the correct formula but substituted wrongly. Those that substitute correctly evaluated it wrongly. The expected answer is:
eV = 1/2mv²
1.6 x 10-19 x 2500 = Yz x 9.1 X 10-31 x v²
v² = 8.79 X 1014
V = 2.96 X 107 ms²;