To find the variance, first we need to calculate the mean of the given data set:
Mean = (11+12+13+14+15)/5 = 13
Next, we subtract the mean from each data point and square the differences:
(11-13)^2 = 4
(12-13)^2 = 1
(13-13)^2 = 0
(14-13)^2 = 1
(15-13)^2 = 4
Then, we find the average of the squared differences:
(4+1+0+1+4)/5 = 2
Therefore, the variance of the given data set is 2. Answer is correct.