8. Incorrect. The answer is false not true.

The confidence interval is

b +/- t*(n-2)^{-0.5}*(s_{y.x}/s_{x}), where t = +/- t_{0.975,6}= +/- 2.45.

0.636 +/-2.45*6^{-0.5}*(0.5641/4.062) = 0.636 +/-0.1389 is the 95% confidence level for b.