In a recent study on world happiness, participants were asked to evaluate their current lives on a scale from 0 to 10, where 0 represents the worst possible life and 10 represents the best possible life. The responses were normally distributed, with a mean of 4.7 and a standard deviation of 2.3. Answer parts (a) (d) below. (a) Find the probability that a randomly selected study participant's response was less than 4. The probability that a randomly selected study participant's response was less than 4 is | . (Round to four decimal places as needed.) (b) Find the probability that a randomly selected study participant's response was between 4 and 6. The probability that a randomly selected study participant's response was between 4 and 6 is | . (Round to four decimal places as needed.) (c) Find the probability that a randomly selected study participant's response was more than 8. The probability that a randomly selected study participant's response was more than 8 is . (Round to four decimal places as needed.) (d) Identify any unusual events. Explain your reasoning. Choose the correct answer below. O A. The event in part (a) is unusual because its probability is less than 0.05. O B. The events in parts (a) and (c) are unusual because their probabilities are less than 0.05. O C. There are no unusual events because all the probabilities are greater than 0.05. O D. The events in parts (a), (b), and (c) are unusual because all of their probabilities are less than 0.05. Find the indicated probability using the standard normal distribution. P(z