Answer:
6.37%
Explanation:
Rate of return 
 = (Aggregate investment value after one year - Investment value) / investment value   ----- equation 1
Cost of shares =number of shares* price per share
              = 1000* $20 =$20,000
Total amount invested = Purchasing cost /(1- front-end load)
                = $20,000 / (1-0.04)
                 =$20,000 / 0.96 = $20,833.333
Investment value after one year 
            = Total Investment*( 1+ price increase-expense ratio)
          = $20,000( 1 +0.12 -0.012)
           = $20,000(1.12-0.012) = $20,000 * 1.108 = $22,160
From equation 1 above
Rate of return = ($22,160 - $ 20,833.333) / $20,833.333
         $ 1,326.667 / $ 20,833.333
 = 0.06368001701
   = 0.0637
 Since rates of return are expressed as %, we multiply the result by 100 to get 
   0.0637*100 =6.37%
My rate of return on the fund will be 6.37% if I sell the shares at the end of the year.