Please explain everything in detail. Used 1 Check-My-Work and a. was incorrect.

Tim and Martha paid $9,400 in qualified employment-related expenses for their three young children who live with them in their household. Martha received $1,600 of dependent care assistance from her employer, which was properly excluded from gross income. The couple had $57,250 of AGl earned equally. Use Child and Dependent Care Credit AGl schedule. Required: a. What amount of child and dependent care credit can they claim on their Form 1040? b. How would your answer differ (if at all) if the couple had AGI of $39,500 that was earned entirely by Martha