Plz solve anyone I having trouble answering this someone respond fast

What are the constants in this expression? -10.6+9/10+2/5m-2.4n+3m

Solve the system of equations. y= 2x y= x^2 - 15

The number if marbles of different colors stored in a hat is listed below: 4 red marbles 10 green marbles 7 blue marbles. without looking in the hat, dan takes out a marble at random. he replaces the marble and then takes out another marble from the hat. what is the probability that dan takes out a blue marble in both draws?