A or c is the correct answer
X from -4 to 4. If it’s wrong I’m sorry I’m Siried it
If I'm not mistaken I believe its
1.) 7/9 = .77
2.) cube root of 8 =2
3.) square root of 5 =2.2
There are two constants in this expression
And if you need an example this is the website I went to: http://www.mathsisfun.com/data/standard-deviation.html