How many electrons are in the nucleus of an atom with the atomic number of 20

20 electrons

Step-by-step explanation:

an atom with atomic number 20 has 20protons. it has 20 electrons because the number of protons is equal to the number of electrons in the nucleus of an atom.

constant of proportionality = 3 and the equation is c = 3p.

step-by-step explanation:

c = kp   where c = amount of caffeine in mg., p = oz of pepsi and k is the constant of proportionality.

substituting the values given:

24 = 8k

k = 3.

the same value of k will be obtained if we substitute the other given values.

for this case we have that by definition, the surface area of a cylinder is given by:

where:

r: it is the radius of the cylinder

h: it is the height of the cylinder

we can also rewrite it as:

where:

la: it's the lateral area

ba: area of the base

option a