Lin and Han’s families provide money for their school lunch accounts. Han starts with $100 in his account. He spends $15 each week on lunches. Lin starts with $25 in her account and does not spend any of it. Her family adds $10 each week to her account. At the end of 4 weeks, who has more money in their account? After how many weeks will Han and Lin have the same amount of money in their lunch accounts?