Originally Posted by
Unknown008
a) Well, you did make a mistake, Nhatkiem. You took displacement as 5.6, though you said that you have to take 5.6-1.2, lol!
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So, another option, you have to find the distance from the wall. You have to find yet another time of flight, using the same formula, this time, the magnitude of displacement will be 5.6, the height from which you shoot. Now, you should have the time as 0.63 s. The distance the pellet travels is then 7.61 m. So your pellet travelled 7.61 m, which is 1.49 m away from the wall.
{Nhatkiem, it is there that your answer miraculously coincides lol! :p}