a. 14, 18, 22, 26.... It is +4
b. 2,430, 7,290, 21,870..... It is x3
c. So it is going -2, -4, -6, -8 so the next one would be -10 which is -13 then -12 which is -25 and so on.
Hope this helps!
Answer:
The psychologist finds that the estimated Cohen's d is 0.583.
Step-by-step explanation:
The Cohen's d is used to calculate the effect size, appied when a null hypothesis is rejected.
It can be calculated for this case of population mean as:

The psychologist finds that the estimated Cohen's d is 0.583.
Instead of subtracting 6 from 12 then dividing they added 6 to 12 & ended up with 18. 18 by 2 is 9.
ABC=50
DCE=65
DEF= I think 115
I hope that helps I would appreciate brainliest if possible :)