There are three subatomic particles known: (1) electron which is found outside the nucleus of an atom and (2 and 3) protons and neutrons which are both inside the nucleus. As they are outside the nucleus, it is easier to transport electron than any other subatomic particle. Thus, atom and its ion differ in the number of electrons.
Answer:
Therefore, the rate of change in the amount of salt is 

Explanation:
Given:
Initial volume of water
lit
Flowing rate = 5 
The rate of change in the amount of salt is given by,
( Rate of salt enters tank - rate of sat leaves tank )
Since tank is initially filled with water so we write that,

Let amount of salt in the solution is
,


Therefore, the rate of change in the amount of salt is 

Alpha particles are helium nucleus ! so answer is A !
it is made by ionization of helium, when both the electrons are out , then two unit of positive charge is one helium and thus called alpha particle !