Chad (51) and Teresa (48) Conklin are married and want to file together. They have two children, Joshua (20) and Suzanne (15), who both lived with their parents all year. They are all U.S. citizens and have social security numbers that are valid for employment. Joshua is single, not a student, and he has a part-time job. Suzanne is single and still in high school. Neither Joshua nor Suzanne provide more than 50% support for themselves. Chad's 2021 wages were $32,786; Teresa's 2021 wages were $20,443; Joshua's gross income was $5,435; Suzanne's was $0. Chad and Teresa had an AGI that was $5,320 less in 2019 than in 2021. Chad and Teresa had no foreign income and $350 of dividends.

What is Chad and Teresa's correct and most favorable 2021 filing status?

What is Joshua's dependency status for Chad and Teresa?

What is Suzanne's dependency status for Chad and Teresa?

Are Chad and Teresa eligible to claim the Child Tax Credit and/or the Other Dependent Credit for any potential dependent?

Are Chad and Teresa eligible to claim the Earned Income Credit?

Are Chad and Teresa eligible to utilize the 2019 lookback provision for the Earned Income Credit?