How can you find the velocity of a bullet fired from a nerf gun the second it leaves the gun, if all you have is the angle it was shot at, and how far it traveled?

(All in degrees)
0 degrees=2.54m
10=6.24m
30=6.54m
45=6.58m
60=1.6m
80=.94m

The range of a projectile fired with speed v at an angle θ is

R = v^2/g sin2θ

So, plug in your numbers and see what drops out for v.