What were the drawbacks of Mendeleev periodic table write any two

1.Position of hydrogen.

2.Placing the heavier elements before the lighter one

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the cdc / centers for disease control and prevention

explanation:

for me i have felt invisible when i was clearly struggling,or,i made a great achievement ,and,nobody took to notice me either because they just didn't see it,or,people just turned their back on me.i can see a person being invisible by choice,or,without choice like i did.the people who are invisible by choice don't try to talk to people,don't try to make friends,and,keep to themselves.i haven't been one of those people so i couldn't give you a reason.

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