Construct a 95% confidence interval for the slope coefficient for Commercial Construction.
A: 1.25 ± 1.96(3.78).
B: 0.76 ± 1.96(0.09).
C: 1.25 ± 1.96(0.33).
D: 0.76 ± 1.96(8.44).
The confidence interval for the slope coefficient is b1 ± (tc × sb1).
答案选 C