[phantomworker]

Ok, technically, you're correct.

Now, what if you dropped a canon ball and at the same time shot a similar canon ball out at a 90 degree angle. Which would land first?

[Sam Hill]

"Now, what if you dropped a canon ball and at the same time shot a similar canon ball out at a 90 degree angle. Which would land first?"

That's popularly called the "Monkey Ball" experiment. Galileo invented it.

And he showed that they land at the same time.

[Right Wing Assault]

Now, what if you dropped a canon ball and at the same time shot a similar canon ball out at a 90 degree angle. Which would land first?

Over reasonable distances and speeds, they hit at about the same time if dropped/fired horizontally from the same level since their downward acceleration is the same (even though the fired ball travels a much greater horizontal distance).

If you drop one cannon ball on the moon and fire the other cannon ball horizontally on the moon at very high speed, it will never hit the moon while the dropped one will.

[JohnBovenmyer]

Now, what if you dropped a canon ball and at the same time shot a similar canon ball out at a 90 degree angle. Which would land first?

All other things equal, in a vacuum over a uniformly dense perfectly spherical body, the shot would land after the drop. The body is curved, so the shot has further "down" to fall. If fired fast enough the shot won't ever land.