Find the missing probability

Click on the number until you find the right quotient. 12x^a y^b ÷ (-6x^a y)

Carmen and matt are conducting different chemistry experiments in school. in both experiments, each student starts with an initial amount of water in a flask. they combine two chemicals which react to produce more water. carmen's experiment starts with 30 milliliters of water in a flask, and the water increases in volume by 8.5 milliliters per second. matt's experiment starts with 10 milliliters of water and increases in volume by 28% each second.

Mr. chen is parking in a lot downtown. the graph shows the relationship between the time and the total cost of parking. evaluate the function for input of 10.