8-5 p411 n27
Original claim: the sample of bumblebee bats come from a population whose mean weight is 1.8 grams
μ = 1.8

The Null Hypothesis
H₀: μ = 1.8

The Alternate Hypothesis
H₁: μ ≠ 1.8

A sample of n = 15 has 14 degrees of freedom.
For a two tailed test and a level of significance, α = 0.05
t_critical = -2.145 and 2.145

Data:
x_= 1.713 and s = 0.2588
t_test = (1.713-1.8) ⁄ (0.2588 ⁄ √15) = -1.302

Because -1.302 is NOT in the Critical Region, we Fail to Reject the Null Hypothesis and the statistical analysis of the data can NOT reject the original claim.

Conclusion:
There is NOT sufficient evidence to warrant rejection of the claim that the sample of bumblebee bats come from a population whose mean weight is 1.8 grams