Answer:
6.4 million students
Explanation:
During the time of 2012-2013, 6.4 million students who are between the age of 6 and 21 have received special education in the united states. These are the children that are suffering from a serious disorder. That's why children that were received special education comprise of 13% students with disabilities.
Due to the special education program, the strength of children increase from 3 year to 9 year
