Differentiate the classification of elements according to Mandelev\'s and Modern Periodic Table

Differentiate the classification of elements according to Mandelev\'s

1.	Differentiate the classification of elements according to Mandelev\'s and Modern Periodic Table
Answer» Why did they flagged me. Can I know the reason? Medelev\'s discover 63 elements .... Mordern periodic table uses atomic no. Instead of atomic mass