P(x) 0.15 1 0.3 0.05 3 0.5 a. Find the expected value of the probability distribution. Round to two decimal places. 1.90 b. Find the standard deviation of the probability distribution. Round to two...

I'm stumped on these 2 questions. THe second picture i only need help with part B. Thank you

Extracted text: P(x) 0.15 1 0.3 0.05 3 0.5 a. Find the expected value of the probability distribution. Round to two decimal places. 1.90 b. Find the standard deviation of the probability distribution. Round to two decimal places. 0.19


Extracted text: A population of values has a normal distribution with u = 125.3 and o = 60.1. A random sample of size 139 is drawn. Find the probability that a sample of size n = 139 is randomly selected with a mean greater than 116.1. Round your answer to four decimal places. P(M > 116.1) =