First, we need to find the number of protons, which is the total mass divided by the mass of one proton:

protons
Then, the total charge is the number of protons times the charge of a single proton:
The answer would be (A) Protons
The pressure exerted by the block on the table is given by:

where W is the weight of the box, and A is the bottom surface area of the box.
The weight of the box is: 
Substituting into the first equation, we find the pressure:

Answer:
-1.2 kg - m/s
Explanation:
And we need to find out the change in momentum of the body . Here ,
- velocity before collision (u) = 10m/s
- velocity after collision (v) = 2m/s .
We know that momentum is defined as amount of motion contained in a body . Mathematically ,
Therefore change in momentum will be,
Since the direction of velocity changes after the collision , the velocity will be -2m/s .