Given a Python dictionary, containing n key-value pairs, what is the complexity of the following (using big 'O' or 'Order' notation)

i) Given a key k, finding the value associated with key k in the dictionary.

ii)Given a key k, checking whether there is an item in the dictionary that has key k.

iii)Given a value v,returning a list of all keys in the dictionary that map to v.

iv) Inserting a new key-value pair into the dictionary.