Questions

Numismatics is the study or collection of currency, including coins, tokens, paper money, and related objects.

A greenhouse gas is a gas in an atmosphere that absorbs and emits radiant energy within the thermal infrared range. This process is the fundamental cause of the greenhouse effect. 

Carbon dioxide is a main greenhouse gas, found in car exhaust pipes.
Methane and nitrous oxide is another type of greenhouse gas.

Oxygen is the only clean gas out there because we need it to survive. Therefore, the only gas that is not a greenhouse gas is Oxygen.

A bureaucracy is a way of administratively organizing large numbers of people who need to work together.

The term bureaucracy literally means "rule by desks or offices".

Organizations in the public and private sector, including universities and governments, rely on bureaucracies to function.

Inhabit means a place or environment to live in for a person or animal or a group.

Vacate, move and reside means to leave a place and are opposite to live. Reside is the only word most nearly means as inhabit.

Management Information Base is part of every SNMP-managed device. Each SNMP agent has the MIB database that contains information about the device's status, its performance, connections, and configuration. The MIB is queried by SNMP.

Town planning, Drainage system and Use of Bronze are the features of Indus Valley Civilization. Use of Iron was not the feature of this.