A researcher performed an experiment with two groups. She found the difference of the means for each group. Then she combined the groups, chose two new groups, and found the difference between the means of those groups. She repeated this process 200 times. The normal distribution of the difference in the means she found is given below. How great would the difference in the means between the first two groups have to be in order to considered significant? A.) at least B.) at least 8 C.) atleast 9 D.) at least 10

answer: 21$

step-by-step explanation:

$42 / $14 = 3   (ratio 3: 1)

$7 x 3 = $21

30 miles

step-by-step explanation:

we know that 60 seconds equals 1 minute and 60 minutes 1 hour

44 ft       60 sec     60 min     158400   ft

  *   *   =

1 sec       1 min       1 hour         hour

we know that there are 5280 ft per mile

158400   ft       1 mile         30 miles

  *   =

1   hour               5280 ft     1 hour

so in 1 hour   it can travel 30 miles

a) 0

step-by-step explanation:

i^413 x i^0 = 0 as any number multiplied by a zero is

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