Which of the following is always true for all probability density functions of continuous random variables? A.They are bell-shaped B.They are symmetrical C.The area under the curve is 1.0 D.They have the same height

Given thatXis a normal variable, which of the following statements is true? A.The variableX5is also normally distributed B.The variableX+5is also normally distributed C.The variable5Xis also normally distributed D.All of the above statements is true