IN A HURRY, only need the correct answer, explanation not needed:

You conduct a randomized controlled trial (RCT) to estimate the average impact of a nutrition program on children's height. Children withT_i=1 were randomly assigned to be in the program (i.e. treatment group), while children withT_i=0 were randomly assigned to not be in the program (i.e. control group).

Suppose for simplicity that you only have 4 children in your study,and consider the following table that provides information on each child's height and whether she belongs to the treatment or control group.

Child ID T_i Child's height (cm)

1 1 125

2 1 127

3 0 114

4 0 119

Assuming the RCT was carefully implemented, the average impact of the nutrition program on children's height is _______?___ cm.