Answer
$(18.21547116,153.84618684)$
Work Step by Step
The degree of freedom is the sample size minus $2$: $df=n-2=29-2=27$.
The critical value is given in the row $df=27$ and in the column with $c=0.95$ of the table. Thus $t=2.052$.
The confidence interval is then: $b\pm tSE_b=86.030829\pm2.052\cdot33.04842$, thus the confidence interval is $(18.21547116,153.84618684)$
