Let X be a normal random variable with a mean of -3.15 and a standard deviation of 3.57. a) The z-score that corresponds to a particular data point (x) is 0.88. Calculate the data point. Give your answer to 2 decimal places. X: b) The area under the standard normal probability density function from negative infinity to 0.88 is interpreted as the probability that X is: 0 less than or equal to x 0 equal to x O greater than or equal to x