What is 50 percent of 84

During how many months was the difference between the number of days with homework and with no homework greater than 6?

Solve the system of equations. y=3x-1 and y=-2x+9. show work

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.