Help brainy please help help help

Consider the set of all four-digit positive integers less than 2000 whose digits have a sum of 24. what is the median of this set of integers?

Solve this system of equations: y=x2-3x + 12 y=-2x+14 4. substitute the values of x, -1 and 2, into either origina equation to solve for the values of y. what are the solutions of the system of equations?

Fracisco's game involves 3 green, 2 yellow, 4 red, and 3 black marbles. if he randomly draws three marbles from the bag, without replacement, what is the probability that he will draw yellow, and then red, and then black? a)1/192 b)1/72 c)3/220 d)1/55