Section 5-104 - Qualifications of voters; residence, gaining or losing1. For the purpose of registering and voting no person shall be deemed to have gained or lost a residence by reason of his presence or absence while employed in the service of the United States, nor while engaged in the navigation of the waters of this state, or of the United States, or of the high seas; nor while a student of any institution of learning; nor while kept at any welfare institution, asylum or other institution wholly or partly supported at public expense or by charity; nor while confined in any public prison.2. In determining a voter's qualification to register and vote, the board to which such application is made shall consider, in addition to the applicant's expressed intent, his conduct and all attendant surrounding circumstances relating thereto. The board taking such registration may consider the applicant's financial independence, business pursuits, employment, income sources, residence for income tax purposes, age, marital status, residence of parents, spouse and children, if any, leaseholds, sites of personal and real property owned by the applicant, motor vehicle and other personal property registration, and other such factors that it may reasonably deem necessary to determine the qualification of an applicant to vote in an election district within its jurisdiction. The decision of a board to which such application is made shall be presumptive evidence of a person's residence for voting purposes.