The effective annual rate is 8.33%.
we can calculate the effective nominal annual rate by using this formula;
r = e∧i - 1
e is the constant = 2.718
i = compounded annual nominal rate = 8% = 0.08
r = 2.718∧ (0.08) - 1
= 1.0833 - 1
= 0.0833 = 0.0833 x 100 = 8.33%