Answer:
1. Hydrogen
Atomic # = 1
Atomic Mass = 1.00794 ( If you round it it's 1.008 )
# of protons = 1
# of neutrons = none
# of electrons = 1
Explanation:
Below is an attachment containing the solution.
I think u can say thats a constant velocity, but remember if ur turning, or going around a curve, that is also changing velocity. Hope this helps have a great day!
1)

<Solve using the formula which is:
Mass=Density×Volume

2)
3)

(Length × Width × Height)


(Answer=7.5)
Answer:
The mass is 
Explanation:
From the question we are told that
The extension of the rod is 
The area is 
The density increase as follows 
The equation 
at

So

=> 
So at
, 
So

=> 
Now

![m = 8 [{2.5 +\frac{ 1.27x^2}{2} } ]\left | 13} \atop {0}} \right.](https://tex.z-dn.net/?f=m%20%20%3D%20%208%20%20%20%5B%7B2.5%20%2B%5Cfrac%7B%201.27x%5E2%7D%7B2%7D%20%7D%20%5D%5Cleft%20%20%7C%2013%7D%20%5Catop%20%7B0%7D%7D%20%5Cright.)
![m = 8 [{2.5 +\frac{ 1.27(13)^2}{2} } ]](https://tex.z-dn.net/?f=m%20%20%3D%20%208%20%20%20%5B%7B2.5%20%2B%5Cfrac%7B%201.27%2813%29%5E2%7D%7B2%7D%20%7D%20%5D)

