Proprietorship firm

I have a query. An individual has two proprietorship firm, if one of them is audited under 44AB of income tax act and the other is not, then while filing return does he file individual balance sheet of both the firms, or just the combined balance sheet? What about Tax Audit report of the is it filled for individual two proprietorship firm or combined for both , if he files individual how does he file because PAN of both the firms are same? Is he files combined than how do we assess the strength of his only one firm