Answer:

Explanation:
Mass of a proton, 
Mass of an electron, 
The distance between the electron and the proton is, 
We need to find the mutual attractive gravitational force between the electron and proton. The gravitational force is given by :

Where G is the universal Gravitational constant

So, the force between the electron and proton is
.
D. F=ma
F is for force, and that equals two things, M for mass and A for acceleration. When mass is accelerated, it gives you force. Force equals multiplying mass and its acceleration.
The answer is donate, therefore elements with positive valences usually donate electrons
Answer:
The value is 
Explanation:
From the question we are told that
The weight of the block is 
The dimension of the block is 
Generally two atmosphere is equivalent to

Generally 1 atm = 
The area of the block would be evaluated using width and height because we need for the smaller surface to be in contact with the ground in order to maximize the pressure and minimize number of blocks
So

=> 
Generally the force due to this blocks is mathematically represented as

Here N is the number of blocks
So

=> 