Consider the experiment of rolling two dice. a) What is the probability of obtaining a sum of four? b) What is the probability of obtaining a sum of five or less? c) What is the probability of obtaining a sum of eight or more? b) Calculate the standard deviation. d) Describe the shape of the diatobutio a) The probability of obtaining a sum of four is (Type an integer or a simplified fraction.) b) The probability of obtaining a sum of five or less is (Type an integer or a simplified fraction.) c) The probability of obtaining a sum of eight or more is (Type an integer or a simplified fraction.) cimal round c) Determine the mode(s) Select the