B1 Students' Book answer key - Dani Pol - EOI CALVIÀ

... 29, t? = 2.045. (c) df = 17, t? = 1.333. 7.2 (a) df = 54, t? = 2.6700. (b) ... b1 ± t. ?. SEb1 = 0.1197 to 0.2456 (or 0.1193 to 0.2461). This coefficient ...