Answer:
The number of atoms is 
Explanation:
From the question we are told that
The mass of coin is 
Number of atom in one mole = 
Molar mass of nickel 
Now the relation to obtain the number of atom in the nickel coin is



Answer:
See the explanation below,
Explanation:
Momentum is defined as the product of mass by Velocity. In this way, we will replace the following equation in each of the cases.

where:
P = momentum [kg*m/s]
m = mass [kg]
v = velocity [m/s]
A)

B)
![P=100*5\\P=500[kg*m/s]](https://tex.z-dn.net/?f=P%3D100%2A5%5C%5CP%3D500%5Bkg%2Am%2Fs%5D)
C)
![P=1200*15\\P=18000[kg*m/s]](https://tex.z-dn.net/?f=P%3D1200%2A15%5C%5CP%3D18000%5Bkg%2Am%2Fs%5D)
D)
![P=15*1000\\P=15000[kg*m/s]](https://tex.z-dn.net/?f=P%3D15%2A1000%5C%5CP%3D15000%5Bkg%2Am%2Fs%5D)
From higher to lower momentum
C,D,B,A
Answer:
Its initial position was 471 m.
Explanation:
We have,
Final position of the object is 327 m
Displacement of the object is -144 m
It is required to find its initial position. The difference of final and initial position is equal to the displacement of the object. So,

So, its initial position was 471 m.