The domain would be [-11,10). -11 has a bracket because there is a closed circle for -11; while 10 only has a parenthesis because there is an open circle. You can use every number between -11 and 10, including -11 (because of the closed circle).
She learned 3 songs in her 12 weeks of summer, so you want to start by dividing the 3 songs by 12 weeks: 3/12 simplify: 1/4 she learned 1/4 of a song each week, meaning the answer is D.