有一组数据怎么用matlab求它的标准差 怎么看它是否符合正态分布呢？请教高手

clc;clear
C=[79 75.625 79 82.75 76.1 78.275 76.325 60.5 69.15 75.175 84.075 63.1 77.1625 76.5765 76.575 68.375];
Std=std(C) %标准差
[F,XI]=ksdensity(C)
figure(1)
plot(XI,F,'o-')

x =randn(300000,1);
figure(2)
[f,xi] = ksdensity(x);
plot(xi,f);

C=[79 75.625 79 82.75 76.1 78.275 76.325 60.5 69.15 75.175 84.075 63.1 77.1625 76.5765 76.575 68.375];
Std=std(C);%标准差
ksdensity(C)