Find the mean, the variance, and the standard deviation of the following data sets:

(a) 1.1, 1.3, 1.5, 1.55, 1.6, 1.9, 2, 2.1; 

(b) 2., .9, .7, 1.5, 2.6, .3, .8, 1.4; 

(c) −2.9,−.5, .1,−1.5, −3.6, 1.3, .4,−.7; 

(d) 1.1, .2, .1, .6, 1.3,−.4,−.1, .4; 

(e) .9,−.4,−.8, ., 1.,−1.6,−1.2,−.7.