95% confident that the true mean difference in mean crying time after being given a vitamin K shot between infants using conventional methods and infants held by their mothers is between and . In other words, the mean crying time of infants given vitamin K shot using conventional methods is anywhere from less than to more than the mean crying time of infants given vitamin K shot using new methods.

Solution :

Two sample T-test and CI : Conventional methods, New methods

Two sample T for conventional method Vs new method

                                                  N        Mean           StDev     Se Mean

Conventional mean                 30        35.3              20.8         3.8

New methods                          30         35.1              22.3          4.1

Difference = μ (conventional method) - μ (new method)

Estimate for difference : 0.17

95% CI for difference : (-10.976, 11.309)

T-Test of difference = 0(vs <): T-value = 0.03   P-value =0.5119  DF = 57

95% confident that the true mean difference in mean crying time after being given a vitamin K shot between infants using conventional methods and infants held by their mothers is between -10.976 and 11.309. In other words, the mean crying time of infants given vitamin K shot using conventional methods is anywhere from -10.976 less than to 11.309 more than the mean crying time of infants given vitamin K shot using new methods.

f(x) = x^3 -2x^2 -3x

x( x^2 -2x-3)

x( x^2 +x -3x -3)

x( x(x+1) -3(x+1))

x( x-3)( x+1)

so zeroes are 0, 3,-1

its (2) option

i believe it is c.y = 9x

rise over run. 9 units up over 1 unit right or 9/1