That would be the proton. The number of protons in the nucleus determine which element it is and its properties.
Work done by me for using force of 4 N to push an object 3 m away is 12 J.
<u>Explanation:</u>
Work done on any object is defined as the force required to displace that object from its original position. In other terms, the work done is the measure of force utilized for moving an object. So mathematically it is represented as the product of force with the displacement of the object due to that force.

Then, here it is given that force of about 4 N is used to displace the object to 3m. Thus,

So, 12 J of work is done by me to push an object 3 m away with the force of 4 N.
.......the answer is a gas