Hi there I am working on a database query and I am absolutely bamboozled as to where to go. I am working on a database practical that deals with a company and its car fleet. There are 6 tables the names of which are in bold:

ALLOCATION: allocation num, car reg, employee num, hire date, return date, mileage used
CARS: car reg, model, engine size, fuel type, insurance, auction value
DEPARTMENT: department num, department name
EMPLOYEES: employee num, forename, surname, address, job, salary, department
INSURANCE: insurance group, insurance cost
SERVICE: service num, car reg, service date, service cost

I have been working on this for about a week and no matter what I do I cant seem to get the result I am looking for.

I need to design a query that will display the amount spent by each department on servicing between two specified dates. I am having trouble as this is dependant on the employee's department who hired the car and so I am complete and utterly lost as I am relatively new to databases.

Your help in this matter would be greatly appreciated.
Thank you