The hearing may be continued from time to time, not exceeding four weeks in all. At the conclusion of the hearing, the board of supervisors conducting it shall pass a resolution, either approving the petition in whole or in part, or denying it. If the board approves it in part only, it shall describe in the resolution the territory proposed to be included in the district. It shall not include in the description any territory, the inclusion of which has not been approved by the board of supervisors of the county in which it is located.