A gun with inertia \(5.0 \mathrm{~kg}\) fires a \(10 \mathrm{~g}\) bullet at a stationary target located \(1.0 \mathrm{~km}\) away. After the bullet leaves the gun, its speed decreases (at the constant rate of accelcration \(a=-1.0 \mathrm{~m} / \mathrm{s}^{2}\) ) so that the bullet hits the target at \(299 \mathrm{~m} / \mathrm{s}\). If the bullet travels in the positive \(x\) direction, what is the recoil velocity of the gun?