Simple prolog problem (beginner need urgent help)

[alfredao2000]

Hey, I am trying to learn prolog but i have few problems. I have some excercises to practice but as i said i have problems with it. Its pretty basic for the specialists but as I said already I am complete beginner.

Ok let me describe my problem:
I have got a database of facts:
bank_income(bank, income)
bank_employees(bank, no_of_employees)
bank_society_1(bank)
bank_society_2(bank)

And now what I need to do is:
1. add up the total income for all of the banks from bank_income(bank, income)
2. show if the entered bank is member of the bank_society_1(bank), bank_society_2(bank),neither or is not a bank.
3. function that displays if the banks are in order of income - bank_income(bank, income)
4. function that displays if the banks are in order of number of employees - bank_employees(bank, no_of_employees).

I hope that you will be able to help me. It will help me to understand it better on working examples, thank you for your time.