Which of the following is an example of frictional unemployment? A. Dora lost her job when the textile mill closed. She does not have skills to work in another industry and has been unemployed for over a year. B. Marsha was laid off from her job with the airline because the recession has reduced the demand for airline travel. She expects to get her job back when the economy picks up. C. George is an unskilled worker who mows lawns in the summer, but is unemployed the rest of the year. D. Hector looked for a job for five weeks after finishing college. He turned down several jobs that didn't use his skills, but now has a job requiring the expertise he gained in college.

Frictional unemployment is the time period between jobs when a worker is searching for or transitioning from one job to another. It can be voluntary based on the circumstances of the unemployed individual. Frictional unemployment exists because both jobs and workers are heterogeneous, and a mismatch can result between the characteristics of supply and demand. Such a mismatch can be related to skills, payment, work-time, location, seasonal industries, attitude, taste, and a multitude of other factors.

Answers A, B, C are examples of structural unemployment. Hector is unemployed because the jobs offering doesn't satisfy his requirements.