A cordless electric shaver uses energy at a rate of 3.7 W from a rechargeable 1.5-V battery. Each of the charged particles that the battery delivers to the shaver carries a charge that has a magnitude of 1.60 10-19 C. A fully charged battery allows the shaver to be used for its maximum operation time, during which 3.12 x 1022 of the charged particles pass between the terminals of the battery as the shaver operates. What is the shaver's maximum operation time?