Ea time one part is randomly selected from a large group of mechanical parts The group contains five types of parts with lengths of 2 cm 3 cm 5 cm 7 cm and 8 cm The probability that a part is selected is proportional to its length A List all possible outcomes treat each length as one outcome and find the probability of eac of them The possible outcomes form a random variable X B Is X continuous or discrete C What is the probability that a randomly selected part has a length of 5 cm or less D What is the probability that a randomly selected part has a length greater than 3 cm