In SQL,

1. How many male and female employees are there?
2. What's the most common first name among
   • all the employees
   • males
   • females
3. What's the most common last name among department managers?
4. What's the mean salary of
   • males
   • females
   • all employees
5. How many employees joined the organization during the last 5 years (starting from the last hire date)?
   • how many of them are male/female?
6. What's the mean age of
   • males
   • females
   • all employees
7. Which departments have more male employees than females and vice-versa?
8. What's the fraction of employees has changed departments in the last decade (starting from the last hire date to 10 years back from that year)
   • male
   • female
   • all employees