Answer
$t_0\gt t_{\frac{α}{2}}$: null hypothesis is rejected.
There is enough evidence to conclude that a linear relation exists between the amount of tar and the amount of nicotine.
Work Step by Step
$H_0: β_1=0$ versus $H_1: β\ne0$
$t_0=\frac{b_1}{s_{b_1}}=\frac{0.05753}{0.00460}=12.507$
$n=13$, so:
$d.f.=n-2=11$
$t_{\frac{α}{2}}=t_{0.05}=1.796$
(According to Table VI, for d.f. = 11 and area in right tail = 0.05)
Since $t_0\gt t_{\frac{α}{2}}$, we reject the null hypothesis.
