A hot air balloon is ascending straight up at a constant speed of 8.80 m/s. When the balloon is 12.0 m above the ground, a gun fires a pellet straight up from ground level with an initial speed of 31.0 m/s. Along the paths of the balloon and the pellet, there are two places where each of them has the same altitude at the same time. How far above ground level are these places? I got 0.628 and 3.90 for my answers and they're wrong! I dont know what I did but I cant find what I did wrong! help please!