Records indicate that the mean weight of mature rainbow trout in Eagle Creek is 1.80 kg with a standard deviation of 0.27 kg. After years of marked oxygen depletion from pollutants in the creek, a biologist wants to see if the standard deviation, σ, of weights has changed. The biologist measures the weights of 16 randomly chosen mature rainbow trout from the creek and finds that the sample standard deviation is 0.38 kg. Assume the current weights of mature rainbow trout in the creek follow a normal distribution.
Does the biologist have sufficient evidence to conclude that the population standard deviation, σ, differs from 0.27 kg? To answer, complete the parts below to perform a hypothesis test. Use the 0.05 level of significance.

(a) State the null hypothesis H₀ and the alternative hypothesis H₁ that you would use for the test.