What materials is not a good insulator

Current enters a circuit at a: 1.positive terminal 2.negative terminal 3.low potential side 4.resistor

What property is a characteristic of a substance that can be observed and does not change the identity of the substance

Acar of mass m goes around a banked curve of radius r with speed v. if the road is frictionless due to ice, the car can still negotiate the curve if the horizontal component of the normal force on the car from the road is equal in magnitude to 101) a) mv2/r b) mg/2. d) mg e) tan[v2/(eg)]