The number of students in a school increases and decreases by 10% respectively in alternate years. If there was an increase in the year 2000, what is the percentage change in the number of students in the year 2003 compared to the year 2000?

In a town with 30,000 professionals, teachers make up 11% of the total professionals. If 46% of teachers are male, what is the number of female teachers in the town?

In a town's professional breakdown, doctors represent 18% and clerks represent 8% of the total professionals. If the number of doctors is 3000 greater than the number of clerks, what is the total number of professionals in the town?