As the carbon content in steel increases, its ductility tends to decrease. a researcher at a steel company measures carbon content and ductility for a sample of 15 types of steel. use the following regression results to find the 95% confidence interval for the slope of the regression equation. the regression equation is

ductility = 7.67 - 3.30 carbon content

predictor coef se coef t p

constant 7.671 1.507 5.09 0.000

carbon content -3.296 1.097 -3.01 0.010

s = 2.36317 r-sq = 41.0% r-sq(adj) = 36.5%

-5.649065  and -0.942935

Step-by-step explanation:

The degree of freedom will be given by

n - 1 where n is the sample number, given here as 15 so

Critical time, t for a 95% confidence interval from the table is  

The 95% confidence levels will be given by

Limit=Parameter estimate ± Critical t * standard error of parameter estimate.

The standard error of parameter estimate is given as 1.097

First limit=-3.296 -( 2.145*1.097 )= -5.649065

Second limit = -3.296 + (2.145*1.097) = -0.942935

3; 9 is 8 to -4

step-by-step explanation:

coins of silver or gold

step-by-step explanation: