I think the answer would be C
Answer:

Explanation:
The original equation is:

We notice that:
- we have 1 atom of Fe on the left, and 2 atoms of Fe on the right
- we have 2 atoms of O on the left, and 3 atoms of O on the right
Therefore, the equation is not balanced.
In order to balance it, we can add:
- a coefficient 3 in front of 
- a coefficient 2 in front of 
So we have:

Now the oxygen is balanced, but the iron it not balanced yet, since we have 1 Fe on the left and 4 on the right. Therefore, we should add a coefficient 4 on the Fe on the left:

Jaydbrbstgsbwiybsbdd to nebsndhbd
vf = vi + at
vf – vi = at<span>
<span>vi= 0, vf=26 and afor nil = 9.8m/s2</span></span>
26 = 9.8t
t =<span> 26 / 9.8 = 2.65 s
Now we know the total time, so we can calculate the time 1
second before it hit the ground.
<span>= 2.65 -1 = 1.65s
<span>Now again using the same equation, vf = vi+at, we can find vf
vi = 0, a = 9.8 t=1.65</span></span></span>
vf = 0 + 9.8(1.65) =
16.17 m/s<span>
</span><span>So,
the nail is traveling with the speed of 16.17m/s 1 second before it hits the
ground.</span>