Determine the 2010 filing status in each of the following situations:

• Michaela and Harrison decide to separate on October 12, 2010. Before filing their 2011 tax return on February 18, 2011, Michaela files for and is granted a formal separation agreement.
• Simon is single and owns a condominium in Florida. His father lives in the condominium, and Simon receives $1,000 per year from his father as rent. The total expenses of maintaining the condominium are $15,000. His father receives a pension of $25,000 and Social Security benefits of $8,000.
• Nick is 32 years old, single, and is a successful investment banker. Peter, Nick's cousin and friend, has fallen on hard times and lives with Nick. Peter works part- time, earns $3,000 and lives with Nick for the entire year. Nick pays the entire cost of maintaining the household and provides $5,000 toward Peter's support.
• Jamal's wife died in 2008. He maintains a household for his twin daughters, who are seniors in high school.
• Kathy and Sven are married with 2 children, ages 14 and 12. In June, Kathy leaves Sven and their children. Sven has not heard from Kathy, but a former coworker of Kathy's tells Sven that Kathy wanted to move to Ireland.