Answer:
2
Step-by-step explanation:
The answer is 2, because there's comparison of the options of ways to buy books.
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:
19
Step-by-step explanation:
20 - 8 = 12
12 + 5 = 17
17 - 7 = 10
10 + 9 = 19