Energy pretty simple but I think I'm missing something

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SUMMARY

The projectile's initial velocity was calculated using the equations for density and kinetic energy. The mass was determined to be 6179.595g from the volume of 326.10cm³ and density of 18.95g/cm³. The kinetic energy of 2.11x10³ kJ was converted to 2,110,000 J, leading to the equation 2,110,000 = (1/2)(6179.595)(v²). The calculated velocity is 26.13 m/s. The discrepancy with the online quiz may be due to significant figures, which should be verified.

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Homework Statement


A projectile that has a volume of 326.10cm^3 is fired with an initial kinetic energy of 2.11x10^3kJ. What is the initial velocity (m/s) of the projectile? The density of the projectile is 18.95g/cm^3.


Homework Equations


D = m/v
E = (1/2)(m)(v^2)

The Attempt at a Solution


1) Use D=m/v to get the mass of the projectile. (6179.595g)
2) Convert kJ to J. (2,110,000J)
3) Use the equation E = (1/2)(m)(v^2) and substitute appropriate data.

2,110,000 = (1/2)(6179.595)(v^2)
2,110,000 = (3089)(v^2)
683.06 = v^2
sq.root(683.06) = sq.root(v^2)

The final answer that I get is 26.13m/s. According to this online quiz, it says that I am getting the answer wrong, but I still have a few more tries.

I don't see what the problem is here, I even tried to convert some of the data into different units, but nothing works. It might be some kind of computer or quiz server problem, so if no one finds anything wrong with what I did, I'll probably have to tell the professor. Any kind of help would be appreciated.
 
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it looks like you did it correctly, although I didnt check your button pushing. Maybe the online quiz is being grouchy about sig figs?
 

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