(must be by hand) A teacher gives a reading skills test to a third-grade class of n = 25 at the beginning of the school year. To evaluate the changes that occur during the year, students are tested...

(must be by hand)

A teacher gives a reading skills test to a third-grade class ofn = 25 at the beginning of the school year. To evaluate the changes that occur during the year, students are tested again at the end of the year. Their test scores showed an average improvement ofM_D
 = 12.7 points withs
² = 100.