The mean price for a gallon of milk in New Orleans is the highest in the country last year at $4.10. A sample from 25 different grocery stores in New Orleans this year found the sample mean price per gallon of $4.20.

Assume that the population standard deviation is known to be $0.40 and the population of milk prices is normally distributed.

Reference: Ref 1

For an alternative hypothesis: > 4.1 and at a 5% significance level,what does the researcher conclude?