Method of producing copolymers by free-radical polymerization of at least one water-soluble N-vinyllactam and at least one hydrophobic comonomer in an organic solvent in the presence of an initiator, where the polymerization is carried out under a gauge pressure such that evaporation of the components is avoided. The fuel card transaction data identifies a quantity of fuel purchased for a vehicle using a fuel card. The cavity has an opening on a first surface through which the foot is inserted. When the second user removes the hold, a notification that the hold has been removed will be communicated to the first user. Ultrasound andor heat is applied to free the microencapsulated components of the two-component adhesive, so that the components of the two component adhesive can react. The Zener diode includes a cathode coupled to the control terminal of the second switching element and an anode grounded.