Dr Kid Is Studying the Effects of Sleep on a Child's

Essay

Dr. Kid is studying the effects of sleep on a child's reading speed. She initially takes a measure of each child's reading speed. Next, she varies the amount of sleep different children get. Finally, she re-measures their reading speed. What is the independent variable in her study?
•initial reading speed
•post reading speed
•amount of sleep
•the difference between the initial and post reading
speeds