LOL at Inquiring minds want to know...
First you want to be honest to the client and yourself especially when it comes to charging your clients.
I understand writing bio-statements for professors, as I use to work at a university. I knew my professors well and could put together a bio-statement within about 30 minutes. That is something I could do quickly and make it good copy. For class information, I worked in the engineering department, so I could also throw together a Syllabus and description of a class as well as the schedule in one brochure in about 1 hour. So, again, it goes back to what you can do within that hour of time, your typing speed, your knowledge of the subject and your research skills.
For instance, my client needs information on drop ship companies that sell medical equipment. I research quite a bit and could get the information she needs within 2 hours. Since med equipment is not easy to find for drop shipping, it would take a little longer to research that subject. But, I could do it within 2 hours and that includes finding the company, pricing, profit, sign up, terms and policy, writing up the email and sending the information to the client.
I hope that helps

Andrea~