Let 𝑥1, 𝑥2, … , 𝑥10 be the observed values of a random sample of size 10 from an 𝑁(𝜃, 𝜎 2 ) distribution, where 𝜃 ∈ ℝ and 𝜎 > 0 are unknown parameters. If
𝑥̅=\(\frac{1}{10}\) \(∑^{10}_{i=1}x_i=0\) and s=\(\sqrt{\frac{1}{9}∑^{10}_{i=1}(x_i-\overline{x})^2=2,}\)
then based on the values of 𝑥̅ and 𝑠 and using Student’s 𝑡-distribution with 9 degrees of freedom, 90% confidence interval(s) for 𝜃 is/are