The length (in centimeters) of the leaf of a certain plant is a continuous random variable with probability density function defined by f(x) = _ for x in [3, 4.2]. Find the mean of the distribution, the standard deviation of the distribution, and the probability that the random variable is between the mean and 1 standard deviation above the mean. The mean of the distribution is cm. (Round to one decimal place as needed.) The standard deviation of the distribution is cm. (Round to two decimal places as needed.) The probability that the random variable is between the mean and 1 standard deviation above the mean is (Round to two decimal places as needed.)