Determine the amount of child tax credit in each of the following cases:

		Child Tax Credit Allowed
a.	A single parent with modified AGI of $213,700 and two child(ren).
b.	A single parent with modified AGI of $78,042 and four child(ren).
c.	A married couple filing a joint return, with modified AGI of $408,104 and four child(ren).