Argus Practice Exam Question

Calculate the General Vacancy for the property in Year 1 of the analysis if we are overriding Tenant 1 and a Percent of Potential Gross Revenue is the method being applied. There is no Absorption & Turnover in Year 1.

General Vacancy Rate: 10%
Total Potential Gross Revenue: $90,000
Tenant 1 Rental: $34,000
Tenant 1 Override %: 0%

I have no prior experience in Argus so this is probably a basic question.

I understand that to get the answer it's (90,000-34,000)*0.10. 

But, I don't understand why it's not 34,000*0.10 
I'd appreciate any help on the understanding of this question as well as understand the Absorption concept in Argus.

Thank you for your help