One of the most common ways to maximize a study's ability to find real differences between groups is to make all efforts to:

the median of the data is 4.

step-by-step explanation:

the median means the middle number of a given number.

to decide which one is the median, arrange in ascending or descending order. but sometimes, you may find two(2) number in the middle, but it's easy, just add them together and divide by 2.

so,   determine the median of the data. 2, 3, 3, 4, 5, 7, 9

it is already arranged, count 3 times forward and 3 backward and the one left is your answer.

2,3,3,4,5,7,9

our answer is 4.

hope this !

answer is b shrapnel injuries

answer; knowledge,reason,and judgement;