Which of the following is an example of a homoleptic complex?

$A$ coordination compound of cobalt contains five ammonia molecules,one nitro group,and two chlorine atoms per cobalt atom. One mole of this compound produces three moles of ions in an aqueous solution. Reaction of this solution with excess $AgNO_3$ yields two moles of $AgCl$ precipitate. What is the ionic structure of this complex?

What is the coordination number of the central metal ion in $[Fe(C_2O_4)_3]^{3-}$?

Which of the following is the odd one out?

The number of ligands which are directly bonded to the metal is known as

Explain the terms 'Coordination Entity' and 'Central Atom/Ion' in the context of coordination compounds.