Convert 12cm to picometers

Aria drove to the store, did some shopping, and then came home. during maria's trip, when was her displacement equal to zero?

Electromagnetic induction. a coil of wire contains n turns and has an electrical resistance r. the radius of each turn is a. initially, inside the coil there exists a uniform magnetic field of magnitude b0 parallel to the axis of the coil. the magnetic field is then reduced slowly. the current induced in the coil is i. how long does it take for the magnitude of the uniform field to drop to zero?

Which radioisotope is used in dating geological formations?