In a regression analysis involving 25 observations, the following estimated regression equation was developed. y-10- +3x2+ 14xalso, the following standard errors and the sum of squares were obtained. sb1 = 3 sb2 = 6 sb3 = 7sst = 4,800 sse = 1,296refer to exhibit 13-9. the coefficient of x2is significantis not significantcan not be tested, because not enough information is providednone of these alternatives is correct.