1) (30%) A manager of an e-commerce company would like to determine average delivery time of the products. A sample of 2

[answerhappygod]

1) (30%) A manager of an e-commerce company would like to
determine average delivery time of the products. A sample of 20
customers is taken. "The average delivery time in the sample was
five days. Suppose the delivery times are normally distributed with
a standard deviation of 1.4 days."
b) The manager claims that the average delivery time of their
products is less than 5 days . Write the null and alternative
hypothesis regarding to the claim of the manager.