Answer:
(b) 0.058 or 5.8%
Explanation:
Given a normal distribution with mean 10.72 and standard deviation 0.14, you want the probability that a value is less than 10.5.
Probability calculator
A suitable probability calculator needs to know the mean, standard deviation, and set of values of interest. Here, ...
mean = 10.72
standard deviation = 0.14
P(X < 10.5)
The calculator shows it to be 0.058, or 5.8%.