Who developed the long form of periodic table?

Atomic numbers of three elements $E_1$,$E_2$ and $E_3$ of the periodic table are $Z_1$,$50$ and $Z_2$ respectively. From the position of the elements shown in the figure,the value of $(Z_2 - Z_1)$ is:

What is the position of copper in the modern periodic table?

What is the number of elements in periods $1$ to $7$ of the periodic table?

$Zn$ belongs to which group in the periodic table?

The element with atomic number $12$ belongs to ......... group and ......... period.