Property Law

Theresa leased a one-bedroom apartment from Landlady for one year at $500 per month. After three months, she vacated the apartment. A family of five wanted to rent the apartment, but Landlady refused.Three months later—six months into what would have been Theresa’s term—Landlady managed to rent the apartment to Tenant for $400 per month. How much does Theresa owe, and why?