Jack and Jacki's son, John, is a full-time student at a University. John earned $7,200 during 2016, which he contributed toward his own schooling and other support. Jack and Jacki also contributed $400 per month toward John's support. May Jack and Jacki claim an exemption for John on their joint return? Why or why not?

Suppose above, Jack and Jacki are eligible to claim an exemption for John on their tax return. Will John be entitled to claim an exemption for himself on his own return?