Which elements were decribed as the transition element by mendeleev.

1. N

2.Ni

3.Ne

4.None

I think its Ni but i think there were no transition element in mendeleev's periodic table please help me
i will mark you as branliest
plz help.

In the particles are arranged in a regular, repeating pattern. a)a crystalline liquid b)a crystalline solid c)all gases d)all solids

The human eye contains a molecule called 11-cis-retinal that changes shape when struck with light of sufficient energy. the change in shape triggers a series of events that results in an electrical signal being sent to the brain that results in vision. the minimum energy required to change the conformation of 11-cis-retinal within the eye is about 164 kj/mol.

What is the main reason why some developing countries fear the increase the free trade policies around the world?