Jupiter Systems, an information technology company, determines that most problems handled by employees at its help desk can be resolved within 20 minutes. The company sets 20 minutes as the standard time for resolving a customer problem. If an employee solves a customer's problem in less than 20 minutes, the employee still earns 20 minutes' worth of wages. Which of the following payment methods does this scenario illustrate? Question 16 options: 1) Standard hour plan 2) Performance bonus 3) Piecework plan 4) Differential plan