raising pay of workers question

[king03]

hi guys please refer to the printscreen to see the complete instructions of what I need to do.

So far I can now display how many workers are hired before a certain date let's say: workers hired before january 1 1990, the code for this is the following:

select count(employee_id) 
from employees 
where hire_date < '01-jan-90'

now I am having problems with displaying some more important things, it is the instructions in the red rectangle on my printscreen. please help me follow the instructions written there. also please teach me how to combine my code above with the code inside the red rectangle. Thanks in advance.

[debasisdas]

You need to include a CASE statement and a group by clause.