Consolidated Balance Sheets (Current Period Unaudited) (Parentheticals) - USD ($)	Feb. 28, 2022	Nov. 30, 2021
Allowance for doubtful accounts	$ 26,748	$ 38,188
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, authorized (in shares)	500,000	500,000
Preferred stock, issued (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, authorized (in shares)	9,500,000	9,500,000
Common stock, issued (in shares)	4,674,671	4,583,504
Treasury stock (in shares)	54,938	44,532

Amount of allowance for credit loss on accounts receivable, classified as current.

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