Hi, John.
1. Assuming that there are 40 working hours per week, you could create 40 tasks, the first one for Monday 9:00, then one for Monday 10:00 and so on up to Monday 17:00, then Tuesday 9:00, and so on up to Fridat 17:00. Give each one a weekly recurrence and set the reminder as appropriate.
2. Create a single task and give it a single context, lets call it >Workhours. Define the schedule hours for this context so that it is open during weekday workhours. Set the recurrence for one hour after completion, and set reminders how you like. The task will appear once per hour as long as you remember to promptly mark it completed when the alarm sounds. Ideally the reminder would only appear at the times that the task appears but somehow I doubt that it would work cleanly. (Monday at 17:00 the task will recurr for Monday at 18:00. Monday at 1800 the start time is reached but the task remains inactive and therefore hidden because the context is closed. The task will appear again Tuesday at 09:00 when the context opens. Will this prevent the reminder from sounding Monday at 18:00 and cause it to sound Tuesday at 09:00 instead? Probably not.)