What is Variable resistance?

What is internal resistance of a cell?

What is the resistance of ideal ammeter.

What is specific resistance of a conductor? How it is related to electrical conductivity?

An electric lamp of 100Omega , a toaster of resistance 50Omega , and a water filter of resistance 500Omega are connected in parallel to a 200V source. What is the resistance of an electric iron connected to the same source that takes as much current as all three appliances, and what is the current through it?

From the circuit the reading of a volt meter is 18 volts. What is the resistance of the volt meter?

The resistance of a Cu wire at 20^@C is 200Omega what is the resistance at 50^@C ?

Define Resistance.