The oxidation state and covalency of $Al$ in $[AlCl(H_2O)_5]^{2+}$ are respectively

In the compound lithium tetrahydroaluminate,the ligand is

$3$ moles of a metal complex with the formula $Co(en)_2 Cl_3$ gives $3$ moles of silver chloride on treatment with an excess of silver nitrate. The secondary valency of $Co$ in the complex is $.....$ (Round off to the nearest integer).

Identify the homoleptic complex from the following:

How can the coordination number of a metal atom in a complex be determined?

Provide the classification of ligands.