or the given probability density function, over the given interval, find the mean, the variance, and the standard eviation. 36) f(x) = 11, [12, 20] 8 36) A) = 15.5; o = 5.20; = 2.28 C) = 15; o = 5.34; = 2.31 B) = 16; = 5.33; = 2.31 D) = 1.6; o = 5.24; = 2.29