Answer:
The answer is "[tex](32.8318736, 29.1681264)[/tex]"
Step-by-step explanation:
When the [tex]95\%[/tex] of the confidence interval are true population means of the dog weight then:
[tex]=\bar{x} \pm \frac{\sigma }{\sqrt{n}} \times z_{0.05}\\\\=31 \pm \frac{6.1}{\sqrt{30}}\times 1.64485\\\\=31 \pm 1.83187361\\\\=(32.8318736, 29.1681264)[/tex]