If X and Y Are Independent Random Variables Then the Standard

question 215

Multiple Choice

If X and Y are independent random variables then the standard deviation of the random variable $X - Y$ is given by which of the following expressions?

• A)SD(X)- SD(Y)
• B) \(\sqrt { \operatorname { Var } ( X ) + \operatorname { Var } ( Y ) }\)
• C) \(\sqrt { \operatorname { Var } ( X ) - \operatorname { Var } ( Y ) }\)
• D)Var(X)+ Var(Y)
• E)SD(X)+ SD(Y)