Answer
$\text{If Set A is equivalent to the set of (even_natural_numbers)}$
then $n(A)=N_{0}$ is not true
$n(A)=\frac{N_{0}}{2}$ should be true
Work Step by Step
$\text{If Set A is equivalent to the set of (even_natural_numbers)}$
then $n(A)=N_{0}$ is not true
$n(A)=\frac{N_{0}}{2}$ should be true
