8. For every service request category, list the category description, the number of requests for that category, the average estimated hours, and the average spent hours (only include spent hours in the average when the number of spent hours is not 0) be sure to format appropriately.

9.List the names for all owners, in alphabetical order, who have a boat in a slip that is larger than the average slip.

10.List the marina name, length, and calculate the total rental fees Alexamara receives each year based on the length of the slip for each marina.

Do numbers 11-21 below. After each change is made, execute an appropriate query to show that the change was made correctly. In other words, for number 11 you should have the create and alter table commands, and for number 12, have the insert command as well as the select command to show the records.

11. Create a LargeSlip table with the structure shown below. Be sure to specify what happens if a corresponding record with a PK is updated or deleted.

Column Name	Type	Length	Dec. Places	Nulls?	Description
MarinaNum	Char	4		No	Marina No PK, FK-Marina
SlipNum	Char	4		No	Slip No in the marina - PK
RentalFee	Dec	8	2		Annual slip rental fee
BoatName	Char	50			Name of boat currently in slip
OwnerNum	Char	4			Number of boat owner renting slip, FK - Owner

12. Insert into the LargeSlip table the record information for all boat/owners whose length is 40 feet.