Answer:
0.0930
Step-by-step explanation:
Given that one of your friends is testing the effect of drinking coffee on the duration of cold symptoms. The common cold lasts, on average, 6 days.
she tests a one-sided alternative about the population mean cold duration when drinking coffee, H0: μcoffee = 6 Ha: μcoffee < 6 She finds z = −1.68 with one-sided P-value P = 0.0465.
If hypotheses changed to two tailed as:

(Two tailed test)
Since we have mean difference and std error the same, test statistic would remain the same.
p value for two tailed would be = twice the p value for one tail
=
Answer:
If
and
, then 
Step-by-step explanation:
This is a problem that utilizes both substitution and the order of operations.

Answer: The Last option is the only option equivalent to that equation.
Answer:
d)X=4 or x=-2
Step-by-step explanation:
X²-2x=8
X²-2x-8=0
(x-4)(x+2)=0
X-4=0 or x+2=0
X=4 or x=-2