Simple interest is calculated using the formula: I = prt, where I = the amount of interest earned, p = principal amount, r = rate and t = time. In this case, you know the principal = $2000, the rate = 1.5% or 0.015 and the I = $60, so you are solving for time 't':
I = prt or $60 = $2000(0.015)t
Simplify: 60 = 30t
Divide both sides by 30: 60/30 = 30t/30 or t = 2 years.