Trey has two dependents, his daughters, ages 14 and 17, at year-end (2018). Trey files a joint return with his wife.

What amount of child credit will Trey be able to claim for his daughters under each of the following alternative situations?

(a) His AGI is $103,300.

(b) His AGI is $426,200.

(c) His AGI is $428,900, and his daughters are ages 10 and 12.