X f(x) dx .......=?(x = 1 to 4) x ((1/4) x^(-1/2)) dx .......=?(x = 1 to 4) (1/4) x^(1/2) dx .......= (1/4)(2/3) x^(3/2) {for x = 1 to 4} .......= 7/6. ---------------- E(X^2) =? X^2 f(x) dx .......=?(x = 1 to 4) x^2 ((1/4) x^(-1/2)) dx .......=?(x = 1 to 4) (1/4) x^(3/2) dx .......= (1/4)(2/5) x^(5/2) {for x = 1 to 4} .......= 31/10.
Var X = E(X^2) - (E(X))^2 .........= 31/10 - 49/36 = 313/180. Std. Dev = sqrt(313/180).
I hope this helps!
I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.